Women Within Knowingly overcharged me for exchange items Internet

I placed an order with Women Within via the internet.  It was an order for 3 packages of panties (2 panties in each package). I had a code to take 20% off one package.  They sent the order in two separate packages.  When I got the first package I discovered the panties were huge and way to big for me.  I sent them back completing the paperwork to exchange them for a smaller size.  Seemed simple enough.

To my surprise I was charged shipping and a $7.50 charge for the return. So the one package originally cost me $29 and they refunded me $10 from the return. When I received the one exchange I noticed they charged me the original price which was incorrect.  The smaller size was $5.00 less.  So they charged me the $21.99 when in fact it should have been $16.99.  Knowing I had another package coming with two more packages of panties I called the help line.  I explained to the very rude service rep that this was a mistake.  She agreed that I was charged the incorrect amount for the exchange.  She told me the next shipment with two packages would have the correct amount of $16.99 for each package and that the 20% would be taken off one package as it was in the original order. 

Not surprisely, the second package has been shipped with each package price of $21.99 and NO 20% discount.  To me, this is blatant fraud.  They knew and acknowledged that I had been charged the incorrect amount and told me it would be corrected.  So they also lied.  To add insult to injury I got emails and catelogs promising free returns.  They are all just lies.  This company has done this to me before and sometimes it is not worth the effort to try and correct it since they just lie to you.  They promise lots of discounts and deals, but they do everything to get away with not honoring them.  So it has cost me nearly $100 for 6 pair of panties.

I will never do business with this company again.