iPhone XS screen right side not responding for touching

Hi! Ever since I upgraded to 13.6.1 my screen’s right side faults to respond touching . It’s very strange because it doesn’t work all across the edge straight from the bottom to the top (see the screenshot, I tried to fill a note with a pencil). I actually have to flip my phone and type horizontally because the buttons on the right aren’t reachable. 

Yesterday I tried switching the screen to larger mode in the settings and then switched back to standard and it helped for a while. But then it failed again and remains unresponsive until now. Any ideas what it could be caused by and what should I do now? I didn’t go for repairs service yet cause it doesn’t look like a hardware issue. Thanks!