Touch screen wont work after it was fixed 2 weeks ago

I have a S4 that I took to have the display fixed.

It was working for 2 weeks on wifi then I took the battery out so I could setup & use on sprint.

After that it would not work when you touch the screen.

I was able to to do a factory reset but still have no touch control.

Took back to repair place they put another screen on it worked at first then quit working on touch.

NOW what?