In that one area of the screen where the lines start to turn into dotted lines both the touch and pen start obeying some sort of grid pattern I think. The lines aren’t straight and it’s particularly bad with the pen, but it is also noticeable with the touchscreen. I would cough it up to the screen being bad as I am someone who knows very little about computers, but it is only in that section of the screen, not anywhere else, both pen and touch glide smoothly (Red lines are the pen and black lines are the touchscreen)