I bought a silk dress from Reiss about 2 months ago. Today I wore it for the second time and I have just noticed the seam on one of the sleeves is coming undone and is frayed. This was an expensive dress and I really don't wish to have to send it off for repair. I no longer have the box or the dispatch note it came with but obviously there's an online trail of my purchase. Will Reiss accept a return?