DS Touch Screen

The touch screen is annoying. I always calibrate it and then put in my R4 chip and then try it and it always messes up. Like let's say I want to press here. It always moves a bit to the right or left. I was planning to get a touch screen protector but I can't seem to find any. Is there any other way I could fix the touch screen?

mine does the same,maybe its just a calibration error with the R4.