Airpods dont sync to iPhone 12, but sync to other devices.

Hi bohdabber,

You've indicated several great steps taken. One that was not mentioned is resetting the AirPods. How to reset your AirPods and AirPods Pro reviews the specific process used for that:

1. "Put your AirPods in their charging case, and close the lid.
2. Wait 30 seconds.
3. Open the lid of your charging case, and put your AirPods in your ears.
4. Go to Settings > Bluetooth. Or go to Settings > [your AirPods].

• If your AirPods appear there as connected, tap the More Info button  next to your AirPods, tap Forget This Device, then tap again to confirm.
• If your AirPods don't appear there, continue to the next step. 

5. Put your AirPods in their charging case, and keep the lid open. 

6. Press and hold the setup button on the back of the case for about 15 seconds, until the status light on the front of the case flashes amber, then white.*

7. Reconnect your AirPods: With your AirPods in their charging case and the lid open, place your AirPods close to your iPhone or iPad. Follow the steps on your device's screen."

If the behavior persists after the reset, contact Apple Support directly to investigate further.

Regards.

Thanks for replying, Boh, and that additional info that this helped resolve your issue!

Have a great day and thanks for using the Apple Support Communities!