If the iPad screen is not responding as expected, there are few things you can do. First, thing you can do is restart iPad. There could be a lot of things running in background that could lead to screen not being adequately responsive. So, restart your iPad and see if it fixes things.
If that does not fix, get the iPad out of case and remove any accessories that are attached to iPad. For instance, there could be a USB drive making entire system slow.
Sometimes, a screen protector could be acting up. So, if aforementioned things do not fix the screen, remove the screen guard.
If everything else fails, schedule an appointment at genius bar. If genius bar is not present in your country, get in touch with Apple Support at your local support center. If your iPad is not under warranty or if you damaged the screen, even though that damage was not deliberate, you would be asked to pay a hefty amount. Mind you, the iPad screens, especially the iPad Pro displays do not come cheap and run into many hundreds of dollars.