Loosing faith in battery doorbell

I’ve had my battery doorbell for 3 weeks now. I’ve 4 hardwired security cameras on my house , I bought this doorbell so that I could speak to whoever is at the door when we’re away on holiday.
I’m pretty sure I charged it to 100% when it arrived, after 3 weeks it was down to 33% , granted I have been messing around with it a lot so I gave it the benefit of doubt. 2 nights ago I took the bell off to recharge it ,which I did via the USB port on the back of the home base. After 10 hrs it had only gone up to 63%. My first thoughts were the USB port on the Homebase was low amperage. I put the bell back in place , the window cleaner came to collect his money, he rang the bell , all my Alex’s announced someone was at the door (all good). When I checked the recordings nothing was there. There was a still of him approaching the door but that was it.
I then put the bell back on charge via an apple usb charger. 10 hrs later it still isn’t fully charged (96%). This is a ridiculous amount of time to take to charge it.
The 2k camera is never 2k in a month of Sundays , luckily I bought it from Amazon & have until January 31st to send it back for a refund.
Is this typical of this doorbell or is mine faulty?