Why have my unity UI buttons suddenly stopped working?,UI Buttons Suddenly Not Working

I recently made a main menu in Unity, but now, the buttons won’t work. I was editing another scene and I don’t remember changing anything, but I’ve been reading through so many forums to no avail, please help if you can.,I have been trying to fix this all day, but I made a main menu a few days ago and now all of a sudden the UI buttons won’t work, they don’t get highlighted when I hover over them, nor do the buttons do anything when clicked, the scripts on the buttons have not been touched, please help.

You cant use when you have a ui object over on them,you must put the object below your buttons in hierarchy.

Turns out the canvas wasn’t the same size or location as the buttons, after resizing and relocating it works fine !