I was wondering if you bought the station (especially the WLIP) used or was it new?
If it was used, maybe the previous owner had registered it.
If it is "new" maybe it was a returned unit, essentially the same problem.
If it was new in the box, Davis is probably your only way out.
If it was used, if you can contact the previous owner, maybe he could delete the account? (not sure if this is even possible, I never needed to do this)
Greg H.