If the AirPods are listed under "My Devices" but they are not connecting, try resetting the AirPods. To do this, place the AirPods in the charging case and close the lid. Wait for about 30 seconds, then open the lid and press and hold the setup button on the back of the charging case for about 15 seconds, or until the status light flashes amber and white.
Once the AirPods have been reset, try pairing them with your iPhone or iPad again.
If you have tried all of the above and the AirPods are still not pairing with your iPhone or iPad, you may need to contact Apple support for assistance. See more: https://barcodelive.org/how-to-charge-airpods