Ring doorbell battery not working after new battery

So I have had my ring door for a few years, it is hard wired. Two weeks ago it said low battery and could not see live mode. I took out battery and recharged. Doorbell worked for a week and again low battery again. Then I bought a new battery and put that in. Worked for a few days and now again low battery.
Why is this happening? It is hard wired, is ring bad, what would cause this?
Thanks

If I understand correctly, the Ring doorbells with a battery use the battery as the primary power source and the wires trickle charges the battery. That allows the battery models to work with older doorbell transformers that don’t have the voltage needed for a doorbell without a battery.

On the device health tile, check for transformer voltage. Maybe your transformer is shot?