Steps to troubleshoot the offline malfunction are in the link here.
Deleting a sensor from the panel would be done on the panel screen. Steps to remove a sensor are in the link below. You would need to enter the installer code to access the Installation menu.
This sensor looks like it is reporting as a 345 Honeywell sensor. Is this a new sensor or is it an older existing sensor?
Smoke detectors have a hard end of life date, after the replace by date they will throw repeated malfunctions to the panel and must be replaced.