Ring Doorbell Pro "offline," likely due to dead battery despite working wired transformer

I have a Ring Battery Doorbell Pro, purchased Aug 2024. I installed it, hardwired [existing-transformer powered], to my system with an existing wired doorbell and set it up with 5G Wifi. And also bought & installed a Ring Chime on 2G WiFi. They've both been working OK, and I could see that the Ring Doorbell always reported 100% charge based on the power from the hardwired transformer. Today I saw that the the Ring Pro doorbell was reported as "offline". When I checked the status, it showed that two days ago the battery was down to 2%, so I assume that the battery lost charge--despite power provided by the connected powered hardwire transformer--and the unit stopped working then. However, the Chime is still online. When I press the Ring Pro doorbell (which no longer lights up) button, my wired chime rings and the Ring Chime also does a simple "boing" [not the more elaborate chime I had selected]. This shows that the transformer is still providing power to the doorbell & wired chime, and that some basic signal is being broadcast to the Ring Chime. The most obvious thing is to replace the battery. But I'm sure Ring will agree that a battery, continuously charged from the hardwired transformer, should last more than 7-months. If not, and Ring thinks that a charged battery dying after only 7-months is acceptable, we have a "problem" -- one that I'm willing to report on every review site & forum I can find.