AirPods not holding any charge

My AirPods have suddenly died? They were absolutely fine a week ago, giving me plenty of use between charges.

Now, they won’t hold any charge? When the charging case (with AirPods inside) are plugged into the mains, the case shows on my phone as 100% charged, with the AirPods themselves at almost fully charged, but then, the instant I remove the charging cable, the light on the case turns off, and the case disconnects from Bluetooth as it appears it’s empty of charge? No amount of pressing the button on the back does anything, it doesn’t even illuminate the light.

Have they inexplicably died?