I don't know why my Xiaomi mi 9t pro cannot connect to my car recently, and I got Error 16 - Communication Error in android auto. I got a big red screen in the android auto app. Initially, I thought that is the problem of my COVIDSafe app because it runs in the background. Then I tried to uninstall that to see whether the problem is solved. That is not nothings changed. So, I re-installed the COVIDSafe App. Finally, I remember I enabled the Dual Apps feature in MIUI so that I can have two IG apps opened at the same time. So, I went to settings->Dual App to delete the dual feature, and then android auto is working again!