WH-1000xm2 battery stopped charging

My original headphone battery started dying quickly (it would only last a few minutes after a charge), so I decided to replace with a new battery. When the new battery arrived it lasted a full charge (because it came fully charged) but once it ran out it would not charge anymore. So the problem is likely on the charging board (even the phone red light does not turn on when connected to micro USB). When I looked closely at the charging board, the ribbon cable was a bit melted, so I believe the problem is in it. What is the exact ribbon cable model I have to purchase if I want to replace the one from the charging board?