Player input stoped working

I’m new to unity, and i am working on a 2D game senior project, my player input stoped working after i implemented a character selection screen. The player won’t move with arrow keys or WASD on the game anymore, I didn’t change anything on the main game, only on the selection screen. I am using a Mac which i think might be the issue. I’ve tried everything i can find and i am really stuck, PLEASE HELP!!!