My left ear pod is not working. I've cleaned it, checked that it is charged, and tried to see if it was balanced and nothing is out of the normal.

Hello Krissyk44,

Thanks for connecting with us here in Apple Support Communities. You've done some great troubleshooting so far. Have you also tried resetting the AirPods? This could sometimes address the issue you're facing. See: How to reset your AirPods and AirPods Pro - Apple Support

You might need to reset your AirPods if they won't charge, or to fix a different issue.

1. Put your AirPods in their charging case, and close the lid.

2. Wait 30 seconds.

3. Open the lid of your charging case.

4. On your iPhone, iPad, or iPod touch, go to Settings > Bluetooth and tap the More Info button  next to your AirPods. (If you don't see your AirPods in Settings > Bluetooth, just go to the next step.)

5. Tap Forget This Device, and tap again to confirm.

6. With the lid open, press and hold the setup button on the back of the case for about 15 seconds, until the status light 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, iPad, or iPod touch. Follow the steps on your device's screen.

AirPods can be associated with one Apple ID. If you want to use AirPods (3rd generation) or AirPods Pro that someone else has used, they first need to remove the AirPods from their Apple ID.

Cheers.