Slickdeals is community-supported.  We may get paid by brands for deals, including promoted items.
Forum Thread

Android 15 update says two SIM on S21 FE - can not turn off!

3,887 115 July 17, 2025 at 05:27 PM
Android automatically updated one of the two S21FE to Android 15.
{SM-G990U3/DS (when it was new, I did flash it with the default to get rid of bloatware - this created the DS on the model name.
The box it came with has SM-G990U2
SM-G990UCACXAU}

Prior to this, S21 FE had just one SIM (physical) and one IMEI.
Now it has IMEI 2 as "unknown" - besides can not turn off SIM2 on the SIM manager.

So the result is it shows the carrier name (SIM 1) and displays "invalid card" presumably for SIM2 on the front when u swipe it down.

Tips or tricks to fix this issue - turn off sim2?
Add a Comment
Reply
About the OP
Send Message
ms2000
Joined Dec 2005 L8: Grand Teacher
115 Reputation Points
9 Deals Posted
78 Votes Submitted
3,887 Comments Posted

4 Comments

View Forum Thread

Your comment cannot be blank.

Sign up for a Slickdeals account to remove this ad.

Joined Sep 2007
L10: Grand Master
> bubble2 8,219 Posts
1,897 Reputation
EasyGuy
07-24-2025 at 03:29 AM.
07-24-2025 at 03:29 AM.
DS means Dual Sim version. You flashed the wrong version and now it updated you to the newer DS version that you dont have. My suggestion is to flashed the non DS version again and start over....
Reply
Joined Dec 2005
L8: Grand Teacher
> bubble2 3,887 Posts
115 Reputation
Original Poster
ms2000
07-24-2025 at 11:36 AM.
07-24-2025 at 11:36 AM.
Quote from EasyGuy :
DS means Dual Sim version. You flashed the wrong version and now it updated you to the newer DS version that you dont have. My suggestion is to flashed the non DS version again and start over....
OK, but why would it prevent me from turning off SIM 2 - this is where the prob is.
Samsung says all phones have issues after the update - they are releasing an update soon

Factory reset will revert back?
I meant hard reset not just deleting data
Reply
Joined Sep 2007
L10: Grand Master
> bubble2 8,219 Posts
1,897 Reputation
EasyGuy
07-24-2025 at 09:46 PM.
07-24-2025 at 09:46 PM.
Quote from ms2000 :
OK, but why would it prevent me from turning off SIM 2 - this is where the prob is.
Samsung says all phones have issues after the update - they are releasing an update soon

Factory reset will revert back?
I meant hard reset not just deleting data
Because your phone doesn't have the hardware to support dual sim, so now your software is confused on your hardware not having something that it was programmed to have. I believe you used a "Global" firmware, which in most cases have less bloat than the states firmwares. Am I correct? But the global firmware are usually for phones that have built in dual sim hardware.

So you will have to look up your serial number and find the correct firmware for your phone then flash that over your current firmware, I believe that might be your issue. Please do more research as doing this incorrectly might brick your phone.
Reply
Joined Dec 2005
L8: Grand Teacher
> bubble2 3,887 Posts
115 Reputation
Original Poster
ms2000
Today at 03:08 PM.
Today at 03:08 PM.
Quote from EasyGuy :

So you will have to look up your serial number and find the correct firmware for your phone then flash that over your current firmware, I believe that might be your issue. Please do more research as doing this incorrectly might brick your phone.
Would u able to give me a tutorial on doing this?
SM-G990U2
Metro by TM

THis site did not find the FW:
https://www.imei.info/download-firmware/samsung/

Tried following these steps:
https://www.hardreset.info/device...n-samsung/

Also went here - but still lost as to which is the correct fw?
https://samfw.com/firmware/SM-G990U2

Thanks
Reply
Last edited by ms2000 August 20, 2025 at 03:46 PM.
Page 1 of 1
Start the Conversation
 
Link Copied

The link has been copied to the clipboard.