Based in china! Bad product!

We received a poorly made dress, with loose stitching and wonky seems. When we tried to contact them there was no phone number or address you can only communicate through email which made them very difficult to get hold of. When they did finally reply they offered us a 10% refund. This,for me, was not acceptable and against our basic UK consumer rights, the dress is faulty and a full refund should be given. So we contacted them again communicating our feelings on the matter, asking for a full refund. Joy dress then offered a 20% refund. Again this is not acceptable, so we continued on this cycle for 2 months which became extremely frustrating. Now Joy Dress have told us we should take a 50% refund because if we send the product we will to pay for shipping and customs which will amount to over 50% of the dresses price so we would loose out! Unbelievable the product is faulty it is their responsibility to incur these costs.
So my advice is to deal with a more local company not one based in china!