It’s a real “problem”, and it has a name : “Zombie fingers” !
If you have thick callouses on your fingers or your skin is very dry, it may interfere with the flow of electricity. This can make it difficult for your device to detect your touch, even if you are pressing hard on the screen.
Chances are that if you Google it, you will find shitloads of solutions to this “problem”. However, if the solution is to stop playing guitar we encourage you to not listen !