scrren non-responsive after aplications start. Then responsive again

I just did an iPhone 6s screen replacement. Buttons, touch, sound seem to work ok. I dialed a number and as soon as the application went into phone call mode, the screen stopped responding. After the other side hung up and phone exited call mode, the screen started responding again.

Went into iMessage to type a message. Application came up, screen unresponsive. Let it go to sleep. After wake up responsive again.

Could this be my install or definitely defective part?