Jio Sim not working after one UI 4 Android update in S21 Ultra update today

[SudarshanSupe]

Same jio sim works in other mobile. As well other sim works in Samsung S21

[Jinu1989]

It's working perfectly fine on my s21 ultra after the update... Didn't had any issues after updating...

[samaungmaster]

If it's a us phone then this is now a known issue

See https://us.community.samsung.com/t5/Galaxy-S21/DON-T-BUY-S21-Series-Phones-if-you-want-use-it-outsid...

[AnvayC]

Somehow I am unable to comment on this post. I am facing the same problem with my S21 ultra.

[SudarshanSupe]

Thank you for the link.
Interestingly, another jio and Vodafone Idea India SIM worked without issues. Otherwise, it should not work.

[SudarshanSupe]

Yes, it's USA device

[APS999]

One UI 4 is causing the network to switch from 4G to 2G - VoLTE doesn't work outside US. Check *#*#4636#*#*. In the Phone information tab, you can see IMS status as Not Registered and VoLTE toggle is off. Samsung needs to fix this.

NB: I opened the post in the US Community. I have been having issues since One UI 4 Beta. I have an Airtel sim, so calls get connected through 2G. Since yours is Jio, I think you are left with no other option.

[SudarshanSupe]

Thank you for information.
Interestingly, other jio sim works fine in the same phone device.
Is there any way to go back to Android 11

[APS999]

What did you mean by other Jio sim? Are you able to make/receive calls in Jio? Ideally, you shouldn't since VoLTE is not working for US models in India.

You can go back to Android 11. I think you will need to flash it manually.

[Subham21]

No such issues on my S21U. Wifi calling is turned off automatically after the update I guess. I turned it on manually after the update.