This just happened to me. My headset tuned off while playing and then I couldn't charge it, the was a slashed battery symbol showing up and light was red on the side.
I tried everything nothing worked, but everything was ok ,the cable the outlet all good, so I left it for a few days. I came back and connected it back up to the same charge I always did and it still had the same symbol and light, so I figured that the battery was dead.
I left the charge in the headset and left thinking I need to buy a new one,when I came back few minutes later the slashed battery symbol was gone,the light on the side turned yellow/orange and the baterry was at zero. After another few minutes the battery started charging back up.
That's all I did so basically nothing but it just started working as I described.
Sorry I don't have a really answer but that is what happened to me I hope it helps