Terrible Customer Service

We bought my wedding ring in May 2017 and at purchase they advised that the ring is silver. Yesterday i washed the dishes wearing the ring and after i was done the ring turned bronze. This is not the quality i know i have another silver ring which has never turned bronze when i work with water so why is this happening. My husband returned the ring to the store (Cresta) and the service from the consultants was appalling they treated him as if he is an invalid asking stupid questions like does he bath with shoes on? really is this what you call customer service. They have now advised that they cannot refund or exchange but will contact their quality control and get in contact. I refuse to wait 6 weeks as i was sold an incorrect product.