My AirPods keep flashing green

Two thoughts:

Check there's nothing stopping them from getting a good connection in the case. It seems to think they are charged, then not, then yes....

The battery or something is going, in which case...

AirPods Service and Repair

Learn more about AirPods service options, warranty, and pricing. Click here --> https://support.apple.com/airpods/repair/service

See if any of these help:

Learn how to 'Connect and Use your AirPods and Airpods Pro', click here --> https://support.apple.com/HT207010

'If your AirPods won't connect', click on this link --> https://support.apple.com/HT207

If you can't connect a Bluetooth accessory to your iPhone, iPad, or iPod touch - https://support.apple.com/HT201205

I have tried all the things suggested and I still only ever get a flashing green light - no matter what I do.

My AirPod Pros cannot be seen by my iPhone Xr, and will not connect to my other devices (iPad Pro, MacBook Pro and Apple TV).

The AirPods were working fine on the iPhone and the Apple TV until yesterday.

I have followed the instructions and removed the AirPods from all the devices (including from iCloud were it was under Find My...), but I'm still unable to get past the flashing green