Ring Doorbell constantly ringing

I've just moved in to a new place and purchased a wired Ring doorbell, the same model the previous tenants were using. It was working as expected the 1st day, but overnight it started ringing every 30 seconds when no one was at the door, for several hours at a time. After resetting, re-pairing, and cutting / draining power to the device over the past few days to no avail, I ended up disabling all notifications and doorbell volume for the sake of our sanity. I've just checked the app, and it's still throwing Missed Ring alerts! The device health shows all green. Transformer is 22V-30VADid I get a bad unit?