I have same problem.
No sim card, no signal..
Hope someone can help to fix it.. When flashed old modem file in fastboot mode now it works. Hope next eu roms will be based on working modem files..
I have the same situation bro. My version is miuı 10 (V10.0.1.0.OEBCNFH) STABLE when i enter update device it finds V10.2.1 OEBCNFK.. I chose download it errors says already you have latest.. Seem need to wait more for stable rom update.
Bende de aynı durum var. Tam kararlı değil zaten o yeni...