Postage charged to me twice

I ordered a set of pants creasers with a $1.99 charge for processing fee and shipping and handling charge of $4.99.  I sent a letter on July 10, 2012 with the statement enclosed. The local post office contacted me to pick up the package which was bulky and they charged me $7.33 for postage again.  There was no postage on the package, no return address.  I also sent a portion of the box that said "postage due" along with my letter and statement.  I would appreciate a refund of $7.33 sent to me, Nancy Mueller, 2202 Furlani Court, Lexington, KY 40513  I also called Miles Kimball July 9th and the gentleman told me to write the letter I mentioned above.  My phone number is 859-296-0111