Full Battery. Sport Clip won't turn on unless plugged in; but will stay on & play once unplugged

Battery is full and will indicate charging when plugged in.

Have tried resetting (hold power down 30sec/ press again…) Player won’t respond.

But when I plug the player into usb port and press power it immediately turns on. I then unplug it, and can use the player like normal. However if I power it down (or it does it on it’s own after inactivity) the problem starts again and the player won’t respond until I plug it in again.

I updated the firmware to 1.04, but nothing changed. Clip Sport Go was purchased Dec 2020

Any ideas? The battery doesn’t show any unusual drainage.