"Add a Battery" message in device health

My Ring Gen 3 is almost always showing "Add a Battery".  While I have solar too, there is definitely a battery there, as it works at night!  I also think the charging is working, as I've only had to charge once since last spring - but I would have had expected to have had zero.  And before it went down, I didn't get any alert, it just failed, which seems consistent with having no warning on charge level.When I change the battery, I usually have to hit reset to get it to start up, just plugging in does not give me the magic blue lights.  I've tried cleaning the contacts too, but obviously I can't see which are contacting.I've only got one battery so I can't simply swap and try another.  The only other thing that is not optimal is my Wifi strength is usually just below 80 (currently showing 77).  Alerts are sometimes slow to be delivered.  But Live works fine.Any suggestions on how to resolve this would be appreciated.