Here's the disappointingly inaccessible AirPods 4 reset procedure from #Apple:
1. Open the lid of your charging case.
2. Double-tap the front of the case while the status light is on.
3. Double-tap again when the status light flashes white.
4. Double-tap a third time when the status light flashes faster. When the status light flashes amber then flashes white, you can reconnect your AirPods.