Won't turn on, won't charge (no red indicator light)

Hi everybody ✌️

My headphones don't turn on at all. No lights come on either.

They also don't seem to charge. There is no red light turning on when I plug it in.

I though maybe the battery died after the headphones where in the car on a hot day. But the battery seems fine visually.

I also tied to unplug it for 20mim or so. Nothing changed.

I checked the USB board visually but it seems fine too.

The flexcable connecting the USB board with the Mainboard in the right earspears looks a little suspicious. It looked like this already before I pulled it out. Maybe that's the issue? 🤔

I just don't know where to get the right one. I'm located in Germany.

Does someone have an idea? That would be awesome.

Cheers Sam