Poor Quality Fabric return policy

Hi guys. We bought this fabric so that my wife could make a dress for Christmas. After making the dress and giving it a light bucket rinse to be worn the colour started to fade. She still wore the dress fir Christmas and after another wash the colors faded. Upon approaching the store the staff were satisfied that this material and another similar one was problematic. This was also pointed out by a local tailor in the store at the time. He said this material should be dry cleaned and not washed. I do have a refund slip to be paid via eft but am told now that there are no refunds on cut material irrespective of the quality. Boss fabric sells good quality material from my previous experience however the policy of no return for poor quality fabric is not acceptable. Can anyone help me resolve this in an amicable way.