Wired in 2k battery powered doorbell had turned off due to low battery?

I’ve had the doorbell for 2 weeks. When it arrived I charged it fully then realized I could wire it into my home with my current doorbell chime in the house and I loved the option. I also read in the manual it will also continually charge the battery so I don’t have to worry about battery consumption. Well they were wrong about that one because it’s now turned off due to low battery even though it’s wired into the home. Now idk what to do besides unplug it to start using the battery. Any suggestions or help you all could offer would be greatly appreciated. Thanks!