Ring contact sensor offline

I have had my ring alarm for 2+ years with no issues. Last week, one of my Gen 1 contact sensors for a door went offline. It is not far from the base and I have a range extender in that room. I removed and tried to re-add, etc. all with no luck. Battery is not empty and I tried with fresh battery to be sure. I ordered a replacement Gen2 and was able to get that configured. Then the old one started working and I moved it into a garage side door (even further from base station) and it works more reliably now for some reason. The new Gen 2 did go on- and off-line a few times at first and has failed to report door open/closed a few times when showing online. Now my front door sensor Gen 1 is offline. It is probably 5 feet from the base. Again, I have never had an issue with any of the devices going offline prior to the past 2 weeks. Could it be my base or any other tips?