Doorbell 2 disappointment

Bought a Doorbell 2 and official mains transformer and basically the battery was dead last week (down to 3%) HAD assumed it would keep it topped up. Recharged it last weekend and already down to 50% which is ridiculous, wish I had not bothered spending the £20 on the mains transformer as it is a waste of time if you need to take off the bell to plug it into an external charger !!!

As some background, ordered it and the end of November and it lasted about 10 weeks on the initial usb charge plus mains charger / hardwired.
Down to 3% by last Sunday and plugged back in Monday morning at 100% and still hardwired, is it faulty if the battery is already down to 50% ?

Hi @Qwakuk. There are a few things to consider with expectations for the battery life of your Ring doorbell. First, your Motion Settings and Motion Frequency will determine how often your doorbell activates. If you are expecting more that 18 activations per day, you can experience battery drain quicker than average. The RSSI of your device also plays a factor with battery. A poor RSSI will cause your device to work harder to transmit information, causing excessive battery drain.

Lastly, you’ll want to make sure that your doorbell transformer is at least 16VAC 30 VA. If it’s not, it might not be sufficiently providing a trickle charge to your device. I would consider these things when determining the cause of your battery drain. If you made changes to your doorbell but are still experiencing excessive battery drain, reach out to our support team for the next best steps.

The mains charger is the official product sold by Ring. I have significantly reduced the motion activity field.

The battery is not draining now after reducing the field BUT I fail to understand why it lasted 10 weeks on the initial charge and then drained rapidly in less than a week after a second usb charge.