How To Permanently Stop Multiple Apple ID Prompts?

Hello all,

I recently had to restore my phone from an icloud backup. Ever since, I get prompted every time I join a new network to enter passwords for accunts that have long since past. I am sure it is because there must be a song in my 24,000 song library or an app from a previous account or a friends account back in the day that we shared.

It seems the solution I see mentioned is to delete this items from the library. That said, how do I figure out which files are the culprits? I've seen going in and right clicking each file and seeing properties etc... but there is no way in **** I can do that for this size of a library!!!

Please help, I am being prompted every so often for 5 different account log ins and I am ready to kill my phone.

Have a great day!

Rob