How/why is my device becoming tampered while armed?

My alarm was just set off by a sensor on an exterior door becoming tampered. This device has been a pain about saying it is tampered when I try to arm the system, especially if my bad station goes offline for some reason (such as power going out for more than a few seconds or Wi-Fi connection being down for any period of time). When I check the sensor through the app, it shows full battery level. Can anyone tell me why this one sensor keeps becoming tampered? Could the sensor need to be replaced? It was quite the shock for the alarm to be triggered at 12:50 am by this sensor.

Hi @user15858. A tampered Contact Sensor means that the cover is not on all the way. You can learn how to clear this error by reading this Help Center article here. I hope this helps!