iPad Pro screen sensitivity

the touch screen works by capacity as in electrical charge of ones fingers

light have no impact, maybe if you have dryer skin at night it could explain it

attempting to apply some moisture lotion to ones hands would be what my first troubleshooting would be

My mom has a degenerative nerve disease that over time has reduced the electrical impulses in her hands and finger which has reduced the electrical capacitance in her fingers to reliably transfer those electrical impulses from her fingers to the iPad's screen.

She uses an ordinary, run of the mill capacitive aluminum stylus that seems to help amplify and transfer her fingers' electrical impulses to the iPad's touch screen much better.

Maybe you should try using any type or brand of common capacitive stylus to use with your iPad.

They even make fine point battery operated capacitive style stylii (called "active stylii", different from Bluetooth stylii)i, that make generated electrical impulses from the battery form around the finer tip of the stylus to get finer stylus control on the iPad's touch screen.

Good Luck to You!