topic Nov 26 update killed my S21 phone service in Galaxy S21

No cell service after UI 8 update

Mags2018 — Wed, 26 Nov 2025 15:13:09 GMT

I found a lot of posts about this. Has anyone found a solution? Frustrated.

Re: No cell service after UI 8 update

Dan2023 — Wed, 26 Nov 2025 21:34:00 GMT

Have you contacted your carrier?

You pay your carrier for network connectivity, not Samsung, and your carrier is supposed to test an update on their network before releasing it to their users.

If there is an issue like yours, then the carrier should work with you to fix the problem amd/or they may have to work with Samsung to obtain a patch to resolve the issue.

Re: No cell service after UI 8 update

XCalebur — Thu, 27 Nov 2025 02:50:09 GMT

Factory Reset was the only thing that worked for me.

Update knocked out phone service

userxb0FKi83xR — Thu, 27 Nov 2025 18:20:26 GMT

Galaxy S21, system updated and now I can't make or receive phone calls. No dialtone. Straightalk is my provider and I can't get anywhere with them. I can get texts and can communicate thru messenger on Facebook. I do have internet. HELP!!!

Re: Update knocked out phone service

Mujibar — Fri, 28 Nov 2025 05:03:47 GMT

Clear device cache. Also reset mobile network settings.

Re: Update knocked out phone service

userxb0FKi83xR — Fri, 28 Nov 2025 15:31:06 GMT

Thank you for answering but I don't know how to do that.

Re: Update knocked out phone service

AlejandroMedrano — Sun, 30 Nov 2025 00:42:50 GMT

I am having the same issue but when It says I have no sim card my phone restarts on its own

One UI 8 update — S21 FE lost IMEI / No service

dig814 — Mon, 01 Dec 2025 03:29:29 GMT

After installing the One UI 8 update on my Galaxy S21 FE, the device immediately lost all cellular service.

IMEI now reports as “Unknown” and all network/APN settings are disabled.

The SIM works in other phones, and this occurred immediately after the update.

Multiple users are reporting the same issue on Samsung Community.

This appears to be a modem/baseband firmware failure introduced by the One UI 8 update.

Request modem hotfix or rollback.

Re: One UI 8 update — S21 FE lost IMEI / No service

meself — Mon, 01 Dec 2025 03:35:13 GMT

Seems to be affecting several models I would submit feedback

Re: One UI 8 update — S21 FE lost IMEI / No service

dig814 — Mon, 01 Dec 2025 03:56:26 GMT

I did already. Thanks. Just trying to be the squeaky wheel.

Re: Re: One UI 8 update — S21 FE lost IMEI / No service

meself — Mon, 01 Dec 2025 03:59:38 GMT

Not sure what caused it

Re: One UI 8 update — S21 FE lost IMEI / No service

userxb0FKi83xR — Mon, 01 Dec 2025 04:08:51 GMT

I have the same problem

Re: Update knocked out phone service

userxb0FKi83xR — Mon, 01 Dec 2025 04:11:41 GMT

Yes mine doesn't show a sim card. How is this matter getting taken care of? I've been without a phone for about 5 days now!!! What can we do?

Re: One UI 8 update — S21 FE lost IMEI / No service

Omotara — Mon, 01 Dec 2025 04:42:11 GMT

They need to act fast on this, support acting like they ain't aware of the issues.

An update to rectify is needed urgently.

Re: One UI 8 update — S21 FE lost IMEI / No service

dig814 — Mon, 01 Dec 2025 04:45:20 GMT

They are definitely aware. They admitted it immediately when I asked but there seems to be no sense of urgency for a fix.

Re: One UI 8 update — S21 FE lost IMEI / No service

no2iphones — Mon, 01 Dec 2025 10:51:25 GMT

New update is horrible

Re: One UI 8 update — S21 FE lost IMEI / No service

Roadrunner68 — Mon, 01 Dec 2025 16:04:58 GMT

Call t mobile and its on the sim chip

Re: Re: One UI 8 update — S21 FE lost IMEI / No service

dig814 — Wed, 03 Dec 2025 00:36:48 GMT

I've tried 3 times to submit an error report. All three posts were different and had different information of various lengths. No matter what I say I get the same canned response, so clearly they don't give a **bleep**

Re: Re: Re: One UI 8 update — S21 FE lost IMEI / No service

meself — Wed, 03 Dec 2025 00:38:47 GMT

Think those are replies they send everyone dont get discouraged tho

Nov 26 update killed my S21 phone service

jfm30204 — Wed, 03 Dec 2025 13:15:54 GMT

Verizon couldn't fix it. Samsung chat said submit error report via Members app, which I did 2 days ago. It has apparently been deleted. I have now been without cell service for more than a week. If Samsung doesn't help me, there will be no more Samsung phones in my future.