Tampered contact sensor

HiI recently purchased an additional 2nd gen contact sensor for a kitchen window. I installed the sensor and immediately received a tamper notification, and now I can’t get rid of it.I have tried/checked the following:- Reconfigured device- Removed device and re-added- Checked for the “click” when sliding the sensor back on its mounting plate- Checked that the sensor is stable, not moving and feels secure- Checked that the sensor has ample signal - it’s in range of both the base station and range extender (there are sensors further away that work fine too)The sensor obviously works because when I open the window, it does it’s job.Is there any way of removing this tamper notification? My system is all 2nd gen.ThanksBen