My Apple ID isn’t letting me open it why is that

I while ago I had someone from Apple fix my phone because all my contacts use to be synced up with my parents so we have that fixed and everything was fine until I went onto the App Store and iTunes when I tried to buy apps and songs. It just would not let me buy it. I would be able to type my password but every time I pressed install or download it woukdtn do anything acting as if I didn’t press the button. I had gone onto my setting and tried to access my Apple ID but I actually couldn’t event get into Apple ID setting because it is a light grey colour as if it was locked. I really need help with this I don’t understand how to fix this.