I have a Ring Doorbell 3 and until last week it was brilliant. Its been running for a year with no problem.
Its hard wired and never dropped below 98% battery.
Last week I checked the health to find it had 20% battery so I charged it and three days later it was down 45% So I ordered a new battery to rule out a dead cell and with the new battery the same issuè occurs.
No change to the config and the device shows that it is hard wired. I have metered the bell wire and get 18v AC.
I turned off all motion detection and recording and still the battery drains.