Recovering deleted Auth codes

The codes were on my Microsoft Authenticator for apps and sites requiring 2FA. I remember changing my phone number because I lost my phone and I accidentally deleted my codes because when downloaded the app on my new phone because the codes were not showing up and I thought that I need to reset my backup codes in order for the to show up but I guess that made things worse.

Thanks for clarifying.

Since these were Microsoft Authenticator codes for different apps and websites, the phone number change will not bring those codes back by itself. Those codes are tied to the Authenticator app backup, not just the phone number.

On the new iPhone, please check first if you are signed in with the same Apple ID/iCloud account that was used on the old phone. Also make sure iCloud Drive, iCloud Keychain, and iCloud Backup are enabled.

Then try reinstalling Microsoft Authenticator and check if it gives you the option to restore from backup.

If no backup appears, or if the backup was deleted/overwritten, those deleted 2FA codes usually cannot be recovered. You would need to go to each affected app or website and use their account recovery option to remove the old Authenticator setup and add it again.