Perhaps the axle was reversed when re-installed (i.e. what was the freewheel end of the axle is now the fixed end)? Or all the hardware was removed from the axle when serviced, instead of just one side? Removing everything from the axle makes it trickier to get the offsets right when reinstalling. Removing only one side's cone, washer(s) and locknut, and remembering which end (fixed or freewheel) it came from, means reinstallation uses the same offsets as before service.