After MIUI update 12.5.2 1st Aug, 2021
1.Proximity Sensor not working during phone call and also tested during Xiaomi inbuilt CIT test ( Failed to test cover the screen, constantly showing 5.0).
2. Auto Brightness not working properly day to day usage.
I already generated log file and reported to Xiaomi developers. Request to all do the same if you have same issue..
If anyone having same problem type 'yes' in comments....