Phone "go back" and "loaded app" buttons now need extra press?

Hi

Last week I changed my original LCD screen because the original one had issues in the cold. I had to rub it hard to make it hot to bring the light.

Now after changing the lcd, I have to press the go back and loaded apps buttons harder with my finger. Both used to work with very limited touch before. I have enabled touch sensitivity but still the problem persists. Any solution?