I have the Ring 3 pro. I have had it for over a year with not problems charging until about two weeks ago. It has been hard connected to the doorbell wires since I have owned it and has always keep the battery charged. The weather is warm and I have a good wifi signal. I just took it apart to charge the battery and check that the wires were still connected and no corrosion.
There are other long posts on this with tons of comments. The majority thinks it was a firmware update that broke it. Ring has yet to resolve it.