Contact sensor 2

Hi I have two ring contact sensor 2 and they are both saying tampered, I have recently moved house and they might have got knocked but they are not damaged.I have tried removing the batteries and pressing the little button with a pin and removed them from my system.Once connected back to my alarm the tampered light goes off then seconds later comes in again.Finally when I go to set my alarm as I leave the house on the app it states both sensors have been tampered and I need to bypass them, making them both obsolete.Has anyone got any ideas of how I can solve this issue please.Regards Marc