Could be a couple of reasons it isn’t working.
The activity zone should be set up correctly.
The sensitivity could be too high, check the Power Manager stats for that. If it has many false events, the doorbell performs less to save battery.
The Power Manager profile can also play a part in this. Which one is active?
The app should not be battery optimized, otherwise the operating system could kill the app in the background and you don’t get notifications.
Remove activity/ignore zones if you have any, ensure the right sensitivity setting is selected and give it a try.
You can contact support@eufylife.com for additional support.