Hi Jeanne Marie,
  Sorry to hear that.
  Just in case your store cannot help you out, I want to mention 2 pedals with the polarity switch located outside:
  1.  The Signal Flex pedal (Model # SF2481)
  2.  The Satar pedal (Model # VST 125)
  Both of these pedals are in the $20 US range.
   Hope that you can have this problem solved soon.
   Regards,
   Sean