Home Doorbell 2k not charging

I bought a 2k battery doorbell but I have plugged it into charge for the first time and there’s nothing. I have been told that I should be getting a red light while it’s charging, am I doing something wrong? Any tips to troubleshoot and fix the issue. I have pressed and held the sync button for 10 seconds and nothing

Double check to see if you have inserted the USB cable in correctly on the doorbell.
If you’re charging it via the HomeBases USB port try charging it with an AC USB charger to see if it works. Also try another USB cable.

^^^ this. The 2K dual camera battery doorbell port is “VERY TIGHT” and I really have to shove the cable in hard before the green charge LED kicks in.