Door sensor offline

1 door sensor recently went offline. I have replaced battery and tried to reset but did not fix issue.

Hey @JCovell. Could you try to remove the contact sensor (if Remove Device fails, try "Remove Failed Device) from your system,factory reset the sensor, and then reinstall it onto your system? When re-setting up the sensor, keep the battery out until after you’ve scanned the QR code and it says “pull the tab.” When it says to pull the tab, put the battery back in the sensor and the cover back on. The closer to the Base Station that you are with the sensor during this time, the better.