check and wipe out the very tiny dust particles and oily substances which has covered the front upper side of your mobile(front camera and ear piece grill)
Please follow the below-mentioned steps in order to resolve the issue:-
> Please disable the Show Screen Update option in developer options or completely disable the Developer Option (Setting>>Developer Option>>Show Screen Update).
>Run the device in safe mode and check the issue.
> If still issue not resolved, please register your concern in the Samsung members app (click on “+“icon>send feedback>Error report/ Ask Questions).
