Solved! Go to Solution.
"reverted back to Android 11 and UI 3.1 and it still has the same problem." this implies that it could be something hardware related... but I am just as confused as you might be considering the touch works...
have you tried to use the phone in Safe Mode? if it works fine then it implies a 3rd party app is a probable culprit of this issue.
In such case, reproduce the issue and report to samsung members app > get help > error report asap so that samsung can look into and confirm the cause of issue.
Hello, we are sorry to hear that you are having this issue with your device. If you have already attempted the troubleshooting provided the next step would be to service the device. Please feel free to reach out to us directly via one of the following options and include a link to this thread.
1. Facebook Messenger: http://m.me/samsungsupport
2. Twitter: https://twitter.com/messages/compose?recipient_id=18768513
3. Or you can use the following link below to request service. https://www.samsung.com/us/support/service/
4. UbreakIfix which is a Samsung Authorized walk-in service center: https://www.samsung.com/us/support/ubreakifix
5. Private message: http://bit.ly/2Kq3zL5