I've sent them logs and reports through the feedback app, still no results. It used to work on MIUI 11, I don't know why the can't solve this and push a fix, this is a a basic functionality. I can't use my phone as a phone, ridicilous.
I have MI 9 SE and face the same issue, basically I cannot use my headphones during calls, only when listening to music.
This is super annoying. Anyone found a solution?
I updated to 220.127.116.11 and still nothing. The support was of no help.