Homeshop18 — Whole courier charges not refunded

Website:

www.homeshop18.com

I shopped a product from homeshop18 bit I received the product with fault(missing parts). so I self return the product by contacting the customer care of the site.The courier company charged 600 for the return of the product, before courier the product I called the customer care that it's taking Rs. 600 to courier the product, the customer care of the shopping site told to courier without any hesitation and all your courier charges will be refunded via cheque. After some days I got the cheque but for only Rs. 110. So I called the customer care and told him that the whole amount had not been refunded, this time the customer care told me a different story that according to our company policy we can only refund the 10% of the price of the product against the refund of the courier charges..
this is totally fraud. why should I pay for their fault because the fault was in their product. please look into the matter asap
thanking you
order no. :[protected]