Battery video doorbell (2nd Gen) - NOT CHARGING

I have an issue with my battery video doorbell 2nd Gen. It has been working flawlessly for 7 months, but has now developed a fault. It is mounted to the genuine solar charger and has always been very reliable, barely dropping any battery percentage and always showing as charging The problem It has since stopped accepting a charge from the USB C connection and completely discharged itself. I have removed it from the solar dock and tried to charge it using a number of different known good USB C chargers and cables, as well as leaving it on charge for 10+ Hours and it always remains lifeless with no sign of any battery charging indicator. Currently it is useless and I cannot find a way to get any life from the unit. Any help or advice greatly received. Thank you, Ben