Find my old Apple ID
my ex logged out of my old Apple ID on this phone so I had to sign in with a different one, how do I find the old one and get the backup for it?
iPhone 12 mini, iOS 16
Typically an Apple ID is an email address you have used.
Click on this link to read about ways to find your Apple ID --> If you forgot your Apple ID email address or phone number - Apple Support
or go directly to this link --> https://iforgot.apple.com/password/verify/appleid#
If you still need help:
Contact Apple for help with Apple ID account security "This article provides country-specific Apple Support contact information for customers seeking help with their Apple ID password or other security-related issues."
Contact Apple for help with Apple ID account security - Apple Support
Also look in Keychain, and in a browser's security settings if you use it to automatically sign into Apple when using a browser.
For the backup, click on this link to discover how to restore your iPhone, iPad, or iPod touch from a backup --> Restore your iPhone, iPad, or iPod touch from a backup - Apple Support