Hi Melvyn. Welcome to justanswer.
Try doing a factory reset and then check if the issue is still there or not
Perform a factory reset again and don't enter any Google account. Check after that.
Okay Melvyn. Let me know the results.
Does your screen has a protective layer placed to it like tempered glass or any screen protectr?
Your phone is in warranty, right?
This can be a touchscreen failure. In this case, you are better off asking for replacement instead of trying to fix the screen itself. Since it is in warranty Samsung would address this issue for free
Do you have any other query? If yes, then do let me know.
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