Buttons are not detected on Android [RESOLVED]

This problem happened to me and I noticed that the information is not very specific so I want to share my solution to save you time:

1. it may be that the text of the button is interfering, disables "Raycast Target" in Text. this apparently seems in some cases works but in mine it doesn't

2.we have to verify in the hierarchy that if there is an EventSystem if there is not one we can create it in: GameObject/UI/EventSystem

3.if none of the above worked for you we should go to EventSystem and activate "Force Module Active"

the problem was that everything worked well for me from unity but in the compilation to android some buttons failed, I was confused since the code had no errors, I just did not return "OnClick" although if I changed color the buttons.

it seems like an absurd problem but I take off some time so I wanted to share it with you, I hope it's helpful.