Why am I seeing the error "AirPods Mismatch"? Do I have the wrong AirPod in my charging case?
AirPods automatically connect to any device signed into your iCloud account. But when one or both of your AirPods get mixed up with another pair, your iPhone or iPad will warn of an "AirPods Mismatch".
Open the AirPods case with the AirPods inside next to your iPhone. If the AirPods have been previously paired to your device, the name of the AirPods will appear on the home screen.If you are seeing "AirPods Mismatch", they are not paired to your iCloud account and it means the person who has your AirPods is getting the same error message. The recommended solution from Apple is to exchange AirPods with the other person, restoring ownership of your own wireless earphones.
If you are nearby, the Find My app can be used to locate your missing AirPods. Play a sound to find out exactly which AirPod has been mismatched. If you can't locate the mismatched AirPod you will need to replace the missing AirPod directly from Apple.