I lost my phone in the bathroom and it fell face down onto tiles. After that a part of the screen is nonresponsive when I touch it. Sadly it is the topmost centimeter, so I cannot enter webaddresses and such without turning my phone.

What could this be?
Should I open and check the connections?

Regards, Arve

the touch digitaliser may be broken. in that case it could be repaired with a new complete screen replacement.