Fitbit won't connect

[A-M-M]

Couple of days ago I tried to change the clock face and then the fitbit diamond just flashes on and off. I tried charging it, restarting (wouldn't work), and disconnecting. How do I fix this?

[AlejandraFitbit]

Welcome to the Community @A-M-M and thanks for troubleshooting this issue by yourself.

Could you please be more specific about the diamond you are seeing or provide me with a screenshot? Is it the Fitbit logo? If this is the case, I recommend doing the following from your Fitbit app:

1. From the Fitbit app dashboard, tap or click the Account icon.
2. Tap Set Up a Device.
3. Choose your tracker and follow the onscreen instructions to continue.

I hope this helps, let me know the outcome. 

[A-M-M]

I have tried that but it tells me something's wrong so do this :
- Charge device (I have)
-Restart device (I've tried nothing changes)
-Turn Bluetooth on (I tried it says to turn on device)

All it does is flash the Fitbit logo

[AlejandraFitbit]

Thanks for the information @A-M-M. Do you have access to a computer? If you do, please follow these steps from it:

1. Click the Fitbit Connect icon located near the date and time on your computer.
2. Click Open Main Menu...
3. Click Set Up A New Fitbit Device.
4. Click Existing User and log in to your account.
5. Choose your tracker and follow the onscreen instructions to continue.

Keep me posted.