A validation error occurred for the Bundle ID field in the iOS Developer Console’s Identifiers - iOS App IDs registration flow.

Error Message

An App ID with Identifier 'com.example.xxx' is not available. Please enter a different string.

This error message indicates that the same Bundle ID is already registered. If you’re working with a development company or similar, ask them to delete the registration on their end, and you’ll be able to register immediately.

Basically, the com.example part should use a domain name you own, so there shouldn’t be any duplicates.

That’s all from the Gemba.