Unfortunately in some cases there could be already some data stored on your ViFit® Activity Tracker. Possible cause for that is the unintentional activation during the delivery process. Generally any case of former ownership is not possible.
The data can be deleted through your account on VitaDock Online. Choose "Settings"-> "Account" and click on "Delete activity data".
Please consider that the ViFit® Activity Tracker has an own storage space which contains any registered data for 15 days. If there already is some data on your Tracker please wait until this 15 days are over to avoid another false data transfer.