Doorbell Not Working with Fully Charged Battery

Hi.
I had a Video Doorbell 3+ (plus spare battery) from Feb 2021 which was replaced by a Video Doorbell 4 in Feb 2022. So I’ve now got 3 batteries that I’ve been alternating between.
The battery needed replacing today - the newer battery was in the doorbell and both of the older batteries were fully charged (green light only when connected to a charger). But when I put either of the fully charged batteries back in the doorbell it didn’t recognise either of them - no flashing blue lights as it normally does, and no response even when I held down the reset button for 30+ seconds on either battery.
Is there a short lifespan for the batteries if they’ve been charged quite regularly? I’m usually lucky to get a months use out of a fully charged battery so they get charged quite often. (The newer battery is currently on charge so I’m not able to check it again with that one yet.)
Thanks.

Hi @user32063. All batteries eventually wear down over time and don’t perform as efficiently, but it is a bit odd for a battery to be completely dead after 2 years of regular. Especially given that you are seeing the charging light LEDs when you charge them. About how long are you leaving each battery on the charger, and is it plugged into a standard power outlet?