this is also happening to me. Exactly the same scenario after my last update 2 weeks ago. I was promised a patch by Samsung and T Mobile within 2 days of tech support. It has now been 2 WEEKS and they have not reached back out to me. They took my perfectly working phone and broke it. I am beyond frustrated 😡. This is far and away the worst bug followed by the worst customer service I have ever had. Hopefully this trick works so that I can use my phone. Thanks
I've had this problem on 9/21/2020 - just saying I thought I was going to have to buy a new phone till I did this... who'd have thought it was as simple as turning off the fingerprint sign in? Thank you!