Bad quality of clothes

I ordered a dress from Zando. Upon receiving it, I fitted it on whilst here at work and it was big. I ordered another smaller size and requested a return. Got my new size and it fitted. Meantime I was waiting for Zando to refund me just for them to reject my return saying I wore the dress and showing places where there was marks on. I sent the dress back as I received it, but the quality controllers did not check that the said dress was in good quality for customers to receive it. The replaced dress had a hole in it. I bought another black dress, that dress had no button! Back and forth -e-mails from their customer support. No help. So now I will never ever buy from them again.