I updated my Smart Controller (which I use with my Mavic Air 2) to Fly 1.2.1, having skipped 1.2.0, last week. I can't figure out why, but video transmission no longer works. I get no signal at all in the "transmission" tab. I've tried re-installing Fly, I've done a reset on the controller, I've re-paired the aircraft multiple times, and done multiple restarts of both devices. The transmission still works fine with the original controller and 1.2.1 on my iPhone. Anyone else having issues? This is very frustrating - seems every time I have to do any upgrade on the SC it becomes a major time sink. Photo attached. Any help is welcome!

I have the Smart Controller and MA2, the same as you.  My SC is up to date, yet the DJI Fly App is ver. 1.1.6
How did you install 1.2 or 1.2.1 ?  I didn't think those versions were  compatible with the SC.

I just updated the app through the browser. Thanks!

https://forum.dji.com/forum.php?mod=viewthread&tid=228413

InvisibleName 7 Posted at 11-26 07:33
https://forum.dji.com/forum.php?mod=viewthread&tid=228413

Thanks, all is well again.

Hello there MoreCameras, my apologies this has caused you and thank you for reaching us out. The latest v 1.2.1 for the DJI Fly app that was released recently is not compatible with the DJI Smart Controller. The only option is to go back to the previous version and the version is v1.1.6.
If you have updated the DJI Flyapp from the Smart Controller you can go back to the previous version which is v1.1.6 and it will be resolved in the next version.

Just a helpful steps below to put back the App previous version.
1.Go to "Settings" and tap "Apps";
2.Tap DJI Fly App;
3.Tap "..." at the right upper corner of the screen;
4. Tap "uninstall updates" at the right upper corner of the screen.

I'm glad that all is well now. Always fly safe! Thank you for your support.