Which specs? Fitbits or Garmins? And do you really mean to sync your Forerunner 945 (in which forum you have posted this) with your Fitbit scale? That does not work.
There used to be a service that kept your Fitbit account/weight in sync with Garmin Connect's data, but that has been discontinued (seems it was a third-party service, so neither from Fitbit nor Garmin)
