Impossible to connect my flex to iOS or mac

[scayetanot]

I have followed the guidline, double taping, saw the lights but nothing happens. You can't get it sync.

u try to reboot my device, restarts Bluetooth, fully discharge the flex... nothing

[MarcoGFitbit]

Hello @scayetanot, it's nice to see you around! 

If you haven't tried yet, please restart your tracker and leave it plugged in. Then go to the Bluetooth settings on your phone and check if your tracker is on the list of paired devices. If it is, tap on it and select Forget this device.

While your tracker is plugged in, restart your phone once more and then open the Fitbit app and try to set up your tracker as a new device. Don't worry, the information stored in your account so far won't get deleted:

1. Tap on the Account tab at the bottom of the screen, then tap on "Set up a New Device"
2. Choose your tracker and follow the onscreen instructions to continue
3. If the app asks you to replace your current tracker, please replace it and continue with the process.

Give it a try and keep me posted in case you need anything else!