Left AirPod not charging and case flashing green

Hi

My AirPods are not that old but all of a sudden my left one stopped connecting. Initially i thought it was a flat so I charged it but still nothing. I have tried re-pairing, changing settings on phone, turning phone off and on - the works!

The left airpod doesn't even show up in the Control Centre - just the right one does. It's like the left one has vanished!!

What is the go here? Do I send this to Apple to get a replacement?

Thank you in advance!