Hi bibiana230,
You've done some awesome troubleshooting steps so far! Have you tried resetting your AirPods? Resetting them can help when they won't connect.
You might need to reset your AirPods if they won't charge, or to fix a different issue.
- "Put your AirPods in their charging case, and close the lid.
- Wait 30 seconds.
- Open the lid of your charging case, and put your AirPods in your ears.
- 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.
- Put your AirPods in their charging case, and keep the lid open.
- 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.*
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- 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."
Once that is completed, you can attempt to pair them again.
Check out: How to reset your AirPods and AirPods Pro - Apple Support
Have a good one!