03-11-2016 14:58
03-11-2016 14:58
03-12-2016 03:27
03-12-2016 03:27
Welcome to the Fitbit Community @Kate213! Could you tell me what your tracker shows on the screen when it gets stuck? Some times it can take several attempts before updating the firmware. Check out these tracker update instructions just to make sure that you're not missing any step. If the issue persists, try rebooting your tracker and update it through a PC if available.
I hope this helps. Let me know how it goes.