There is 2 possible issues :
You forgot to include the application code into your Sobipro vCard template. Please refer to the Tutorial for this.
Only Miles, mi or Km appears, but no distance. This is due because you changed the displayed text in backend. By default the value is displayed like '15.5 km'.
But if you need a text like 'You are at 15.5 kilometers', you need to change the backend setting 'custom distance text' from empty to 'You are at %s kilometers'. A common issue is to forgot the '%s' (where is replaced by the distance value).