My Mi 9T Pro global edition for Europe is not usable on WiFi recently.  All my other devices are fine on the WiFi.  Previously, it seemed to work, unless it was really using mobile assisted data?  I recently remember disabling that.

I do remember that I'm pretty certain though that the Miui 11.0.1 update from 10.x.x was over WiFi.  Above, there's mention of 11.0.3.  I don't see such an update when I check for an update.