Old defunct apple id being prompted in new phone

I set up a new phone, restored from icloud, and it is continually asking me for an old defunct apple id. I'm assuming it is because there was some content from my old phone that was bought under this id. I don't have the password and the email address is long gone. How can I identify the content connected with this old id so I can get rid of it and not keep getting asked for it? The apple id listed in settings is correct.