Other Apple ID's purchases in my backup?
Hi folks — yesterday I needed to wipe and restore my phone to fix a recurrent glitch. When I started that process and did the final backup to iCloud, I got something like ten messages that iTunes and App Store purchases (it didn't specify what) from other Apple IDs were in the backup. On each alert it would list the ID, and none of them were anything I recognized (several were just, like "a6wlkj23t@gmail.com"—something that seemed fake).
Once I got my phone set up again and it started restoring, I then got the dreaded "Sign in to your Apple ID" alert for one of these random IDs. You know, the alert that immediately pops up again when you hit cancel. I managed to be fast enough at one point to open Settings and saw that I was already signed in with my correct ID. I could not get the alerts to stop, so finally I did a hard reset, and it hasn't popped up again.
What are these other IDs? Should I be concerned that I got hacked or something? I've never gotten a receipt for a purchase I didn't make. I could guess that the iTunes purchases might have been songs I... did not purchase myself... but I don't see what the App Store purchases could have been.
iPhone 11, iOS 16