bad service

I bought a ring at American Swiss brits on the 28/08/2020 for my girl , two weeks later my girl complains about that the ring changed colour . on the 22/09/2020 I took the ring back to shop, a lady I bought the ring from opted to help and I explain the problem to her. And she is fine she is going to help me . other lady who was helping other customer said to me that I should take care of my ring, with bad attitude she made me feel small in front of my girl the othercustomer