One of my cameras has stopped syncing

[Townsville2018]

I have had 3 cameras for 2 years and one of them has suddenly stopped syncing to the base. I have removed it and tried to sync it to the base at least 20 times. I have also changed the batteries even though the batteries that are in are fully charged

[TomMac]

with a failed sync, sometimes you have to allow the base to reset to sync again....esp if the base sync button is held to long

Pull batteries on camera ( BTW , when new batteries go in and you close the door , does the led flash blue? )

Power button reboot the base , let it come back online ( 2 mins )... put batteries in cam.

QUICK press on base sync button then cam...fast blue means it synced