Repeated "Sign In to iTunes Store" Pop-up
Every few hours/days on my new iPhone8+, I get a pop-up saying "Sign In to iTunes Store", followed by a prompt for the password to my father's Apple ID password. I do not know why I am prompted to enter my father's password - it may have to do with the fact that I was formerly part of some kind of family plan organized by him. I want the pop-ups to stop without having to ask my father for the password to his account.
iPhone 8 Plus, iOS 11.4