Fx chronograph not connecting (suddenly starts working now)

@revoman i already tried everything, i can power it on but it wont connect to bluetooth also i cant lower it off so i have to pull the battery out to shut it off

Make sure all the battery connectors in the battery compartment are touching. Check the see if front antenna board's 3-pins are seated well.

Android or iPhone? Set to "forget" in Bluetooth and add it again.