Updating the firmware on Samsung Duos is not just a way to get new functions, but also a necessary measure for the security of the device. The manufacturer regularly releases patches that close vulnerabilities, optimize battery performance and add new interface features One UI. However, owners of models with two SIM cards (Duos) often have questions: will the second SIM card fail after the update? Will the device get blocked? And most importantly, how to update correctly to avoid errors?

In this article we will analyze all the current update methods - from standard OTA to manual firmware via Odin, and also tell you how to prepare your phone so that the process goes smoothly. We will pay special attention to the nuances for models Galaxy A54 5G Duos, Galaxy M33 5G Duos and other popular devices with support for two SIMs.

If your smartphone has not received updates for a long time, this does not always mean that there are none. Sometimes updates do not arrive automatically due to regional restrictions or operator settings. We will show you how to check available versions manually and what to do if the system persistently writes “No update.”

📊 Which Samsung Duos model are you using?
Galaxy A-series (A14, A23, A54)
Galaxy M-series (M13, M23, M33)
Galaxy S-series (S21, S22, S23)
Galaxy F-series
Other model

1. Preparing your phone for updating

Before clicking "Update", make sure that your phone is Samsung Duos ready for the procedure. Failure to follow simple rules can lead to failures, loss of data, or even bricking of the device. Here's what you need to do in advance:

Battery charge there should be at least 50%. When updating via Odin or Smart Switch it is recommended to connect the phone to a charger - the process can take up to 30-40 minutes, and discharging in the middle of the firmware is fraught with consequences.

Release at least 3-5 GB of memory. Updates for One UI weigh from 1.5 to 4 GB depending on the version. Check the free space in Settings → Device care → Memory. If memory is low, transfer photos and videos to a memory card or to the cloud.

Make a backup copy important data. Although the update does not usually erase files, glitches do occur. Use Samsung Cloud or Smart Switch to backup contacts, messages and applications. Suitable for media files Google Photos or physical copying to a PC.

  • 🔋 Battery charge: minimum 50%, preferably 80%+
  • 📱 Free memory: 3-5 GB on the internal storage
  • 🔄 Backup: contacts, SMS, photos, notes
  • 🌐 Internet: stable Wi-Fi connection (for OTA)
  • 🔌 Cable: original USB-C (for firmware via PC)
⚠️ Attention: If your Samsung Duos is unlocked via OEM Unlock (for example, to install custom firmware), update via OTA may block the bootloader. In this case, use only manual firmware via Odin with file selection HOME_CSC (saves data).

2. Method 1: Over-the-air (OTA) update

The simplest and safest method is over-the-air update (Over-The-Air). The system itself finds and installs the latest firmware, saving all data. Suitable for most users, if there are no regional restrictions.

To check for updates manually:

  1. Open Settings → Software update.
  2. Click Download and install.
  3. If an update is available, confirm the download.
  4. After downloading, the phone will reboot and install the firmware (takes ~15-20 minutes).

If the system says "No update", but you are sure that it is available for your model, try the following steps:

  • 🔄 Restart your phone and check again.
  • 📶 Connect to another Wi-Fi network (sometimes the operator blocks OTA).
  • 🛠️ Clear the update service cache: Settings → Applications → Three dots → Show system → Software update → Memory → Clear cache.
  • 🌍 Check if your phone has a SIM card from a different region (for example, if you have been traveling). Some updates are tied to the operator's country.

Check battery charge (50%+)

Connect to Wi-Fi

Free up 3+ GB of memory

Make a backup of important data

Clear update service cache-->

What to do if the update is frozen? If the logo hangs on the screen Samsung or the progress bar does not move for more than 30 minutes:

  1. Force restart the phone by holding Power + Volume Down for 10-15 seconds.
  2. If the phone does not turn on, try going to Recovery Mode (press Power + Volume up + Bixby with the phone turned off) and select Wipe cache partition.
  3. If this does not help, you will have to flash it through Odin (see Method 3).
⚠️ Attention: On some models Samsung Duos (for example, Galaxy A13 5G Duos) after the update, the priority of SIM cards for calls/Internet may be reset. Check the settings in Settings → Connections → SIM card manager.

3. Method 2: Update via Smart Switch (on PC)

If OTA does not work or you prefer to update via your computer, use the official utility Samsung Smart Switch. This method is suitable for restoring the firmware after failures or if the phone does not turn on (in Download Mode).

Instructions:

  1. Download and install Smart Switch from official website Samsung (the link is easy to find through a search).
  2. Connect the phone to the PC original cable (cheap cables may cause errors).
  3. Run Smart Switch and wait until the app detects the device.
  4. If an update is available, a notification will appear. Click Update and follow the instructions.
  5. Do not turn off your phone until the process is complete (may take up to 40 minutes).

Benefits Smart Switch:

  • 🔄 Ability to roll back to a previous version (if available).
  • 🛠️ Data recovery after a failure.
  • 🌍 Bypass regional restrictions (if the firmware is available for your model in another country).

If Smart Switch does not see the update, but you are sure that it is:

  • 🔌 Try a different USB port or cable.
  • 🔄 Reinstall the drivers Samsung USB Driver on your PC.
  • 🛡️ Disable the antivirus (sometimes it blocks downloading the firmware).
What to do if Smart Switch writes "This software version does not support recovery"

This error occurs if you are trying to flash firmware older than the current one or from a different region Solutions:

1. Download the full firmware for your model via the website SamMobile or Frija and flash through Odin.

2. Check if the phone has a SIM card from another operator (for example, if you bought the phone in roaming).

3. Update Smart Switch to the latest version - old versions. utilities do not support new firmware.

Update method Pros Cons Time
OTA (by air) Simple, does not require a PC, saves data Depends on the region, may not arrive 15-30 minutes
Smart Switch More stable than OTA, you can restore data Need a PC, original cable 30-40 min
Odin (manual firmware) Full control, bypassing restrictions Difficult for beginners, risk of "brick" 20-50 min

4. Method 3: Manual update via Odin (for experienced)

If the first two methods did not work or you need to flash a specific firmware version (for example, to unlock the bootloader), use the utility Odin. This method requires accuracy, but gives complete control over the process.

What you will need:

  • 🖥️ A computer with Windows (Mac is not supported).
  • 🔌 Original USB cable (important!).
  • 📱 Firmware for your model (download only from trusted sources: SamMobile, Frija).
  • 🛠️ Utility Odin3 (latest version).
  • 🔑 Enabled OEM Unlock in the developer settings (if you are flashing custom).

Step-by-step guide:

  1. Download the firmware for your model. The file name should contain the code of your region (for example, SM-A546B_..._SER...where SER is Russia).
  2. Unzip the firmware (usually this is a file with the extension .tar.md5).
  3. Turn off the phone and put it in Download Mode: press Power + Volume Down, then Volume up to confirm.
  4. Run Odin as administrator.
  5. Connect the phone to the PC. Odin a message should appear Added! and a blue indicator in field ID:COM.
  6. In the section Options uncheck the Auto Reboot (if you are flashing BL and CP separately).
  7. Press AP and select the firmware file (.tar.md5).
  8. Press Start and wait for completion (do not disconnect the cable!).
  9. After successful firmware, the phone will reboot. If not - press Power + Volume down for 10 seconds to force a reboot.

Important nuances:

  • 🔹 If you are flashing HOME_CSC, data will be saved. If CSC —the phone will be reset to factory settings.
  • 🔹 For models with Exynos (for example, Galaxy S23 Duos) and Snapdragon (for example, Galaxy A54 5G Duos) the firmware is different - do not mix it up!
  • 🔹 If Odin gives an error FAIL at the stage NAND Write Start, try another USB port or disable the antivirus.
💡

Before flashing the firmware via Odin check the bootloader version (Bootloader) in Download Mode (the first line after the model). If it is newer than the firmware you downloaded, the phone will be blocked. In this case, look for firmware with the same or newer version! bootloader.

⚠️ Attention: On some models Samsung Duos (for example, Galaxy M53 5G Duos) after manual firmware, the setting VoLTE/VoWiFi for the second SIM card may be reset. To return the function, go to Settings → Connections → Mobile networks → [Select SIM] → Enable VoLTE.

5. Frequent errors and their solutions

Even with the right actions, the update may not go according to plan. Let's look at the most common problems and how to fix them.

Error: "Software update is not available" (in OTA or Smart Switch)

  • 🔹 Make sure that your model supports the update. For example, Galaxy A12 Duos (2021) no longer receives major updates.
  • 🔹 Check if your phone has a SIM card from a different region (for example, if you bought the phone while traveling).
  • 🔹 Try changing the DNS on the router (for example, to 8.8.8.8 or 1.1.1.1).

Error: "The software update failed. Try again later"

  • 🔹 Clear the cache and application data Software update in the settings.
  • 🔹 Delete the update file manually: go to /cache/fota via the file manager (root access is required) and delete all files.
  • 🔹 Try updating via Smart Switch or Odin.

Error: Phone stuck on the logo after updating

  • 🔹 Press and hold Power + Volume Down for 10 seconds to force a reboot.
  • 🔹 If that doesn't help, go to Recovery Mode and select Wipe cache partition.
  • 🔹 As a last resort, flash the phone via Odin with a file HOME_CSC (saves data).

Error: After the update, the second SIM card does not work

  • 🔹 Check if the setting Preferred network for the second has been lost SIM: Settings → Connections → SIM card manager → [Select SIM] → Preferred network type.
  • 🔹 Reboot the phone with the SIM card installed.
  • 🔹 If the SIM is not detected, try inserting it into another slot.
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If after the update the phone no longer sees 5G networks, check the APN settings for your operator. Sometimes updates reset the Internet configuration. APN settings can be downloaded automatically in Settings → Connections → Mobile networks. → Access points (APN).

6. How to check the firmware version and available updates

To find out what firmware is installed on your Samsung Duosand check if you missed an update, follow these steps:

Path to information about the firmware: Settings → Phone information → Software information

Here you will see:

  • Android version: for example, Android 14.
  • One UI version: for example, One UI 6.1.
  • Build number: for example, A546BXXU5CXE1.
  • Security date: for example, May 1, 2026.

Deciphering the assembly number (for example A546BXXU5CXE1):

  • A546B - model (Galaxy A54 5G Duos).
  • XX - region code (for example, SER - Russia, XX - international version).
  • U5 — bootloader version.
  • CXE1 — build number (the newer the letter at the end, the fresher the firmware).

To find out what updates are available for your model, use the services:

  • 🌍 SamMobile — firmware database with filters by model and region.
  • 🔍 Frija —a utility for downloading official firmware by model and CSC code.
  • 📱 CheckFirm —an online service for checking the latest firmware by IMEI.
⚠️ Attention: On some models Samsung Duos (for example, Galaxy S21 Duos) after updating to One UI 6.x the ability to use two SIM cards simultaneously with 5G may disappear. This is a firmware limitation - one of the SIMs will only work in 4G. Check the settings in Settings → Connections → Mobile networks → Network mode.

7. Tips after the update

After a successful update, follow a few steps to ensure that the phone works stably:

Optimization:

  • 🔄 Reboot the phone - this will help the system stabilize.
  • 🛠️ Run Settings → Device care → Optimize now.
  • 📱 Check the battery settings: Settings → Device care → Battery → Advanced → Battery optimization.

Checking Duos functions:

  • 📞 Make sure that both SIM cards are detected and you can make calls from each.
  • 🌐 Check the mobile data settings for each SIM.
  • 🔄 If the settings are missing APN, restore them manually or through automatic operator settings.

Data recovery:

  • 🔄 If you made a backup via Smart Switch, restore the data after setting up the phone.
  • 📱 Check if the application settings have been lost (for example, WhatsApp or Telegram may require re-authorization).

Checking new functions:

  • 🆕 Go to Settings → New featuresto find out what was added in the latest update.
  • 🎨 Check new gestures and settings One UI.
  • 🔒 Update your fingerprint/face in Settings → Biometrics and securityif the sensor has become worse.
💡

If after the update the phone begins to heat up or quickly discharges, give the system 1-2 days to optimize. In the first days after the update, background processes may consume more resources. If the problem does not disappear, reset the settings to factory settings (don't forget about a backup!). data-i="325">FAQ: Frequently asked questions

FAQ: Frequently asked questions

Is it possible to roll back the update if the new version works worse?

Yes, but with reservations. Through Smart Switch you can return the previous firmware if it is available for your model. However:

  • Rollback is possible only within 7 days after the update (if there was no data reset).
  • For manual rollback via Odin you need to download the old firmware and flash it with the file CSC (full reset).
  • On some models (for example, Galaxy S23 Duos), the rollback is blocked by Samsung's security policy.

Before the rollback, do backup - the data may be erased!

Why does the mobile data on the second SIM not work after the update?

This is a common problem associated with resetting APN settings. Solutions:

  • Go to Settings → Connections → Mobile networks → Access points (APN).
  • Select a SIM card for which the Internet does not work.
  • Click Reset to default values or add APN manually (you can get the settings on the operator’s website).
  • If that doesn’t help, reboot the phone with the SIM card installed.

On some firmware for Samsung Duos you need to manually enable Data transfer for the second SIM in the mobile network settings.

How to update Samsung Duos if the phone does not turn on?

If the phone is stuck on the logo or does not respond, try:

  • Recovery mode: press Power + Volume up + Bixby, select Wipe cache partition, then reboot.
  • Firmware via Odin: if the phone is running in Download Mode (press Power + Volume Down), flash the full firmware with the file CSC (data erased) or HOME_CSC (data will be saved).
  • Smart Switch (emergency recovery): Connect the phone to the PC, run Smart Switch and select Restore.

If the phone does not even respond to Download Mode, it may need repair.

Is it possible to update Samsung Duos via a memory card?

No, Samsung does not support updating from external media (unlike some Chinese brands). The only official methods: OTA (over the air). and may void the warranty.

  • OTA (over the air).
  • Smart Switch (via PC).
  • Odin (manual firmware).

Unofficial methods (for example, through TWRP) require unlocking the bootloader and may void the warranty.

Why does the update take a long time to download or is interrupted?

Causes and solutions:

  • Slow Wi-Fi: connect to another network or use mobile data (if the tariff allows).
  • Samsung servers are overloaded: try downloading the update later (for example, at night).
  • Operator restrictions: some operators block downloading large files. Try using a VPN.
  • Lack of memory: Free up space on your internal storage (minimum 3-5 GB required).

If the download is interrupted at 99%, clear the cache Software updates and try again.