Here are some fixes you could try when you encounter this issue.
To do this, put it into the charging case.
If the light on the case turns green, the AirPod is fully charged.
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If the light on the case turns yellow, the AirPod is charging.
We’ve noticed that one AirPod sometimes discharges completely, while the other has plenty of charge.
Why does this happen?
Apple
An AirPod that thinks it’s always in your ears is an AirPod that’s always on.
Though both AirPods should charge at the same rate, this isn’t always the case.
pop swing open the case and take a look at the charging bay into which the affected AirPod sits.
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Dust, pocket fluff, and other debris can get lodged and cover up the contacts required for charging.
This will prevent your AirPod from charging, so verify you give it a good clean.
You should also check the AirPod itself.
The silver metallic rim should be shiny and clean.
Take a look at the currently-connected devices.
Do both AirPods appear but you only hear sound coming from one of them?
This could suggest a problem with the speaker itself.
There’s no way of doing this using iOS or iPadOS directly.
Firmware updates happen wirelessly and automatically, as and when they’re available.
Before you do this, you’ll have to remove them from your chosen unit.
Scroll down to the bottom of the screen and tap “Forget This equipment” then confirm your decision.
You don’t need to have your AirPods on or even nearby to do this.
Apple
The AirPods should appear with pairing instructions.
Sometimes, forgetting and re-connecting your AirPods is all it takes to fix the issue.
Look for Damage
Inspect your AirPods and charging case carefully for any tell-tale signs of damage.
You don’t necessarily need your AirPods on or connected for this.
you’re free to also check your AirPods warranty status on theApple Support website.
Take your AirPods to an Apple Store for confirmation of this.