Business ProfileforDesigner Diamonds

I bought an engagement ring set from this jewelry store in the ************ in *******. I was informed by the employee about receiving a warranty for the ring and band. I recently proposed to my now fianc and were getting married in 3 months. Her diamond in her ring recently fell out, I cant find my receipt at this time but I do know that my warranty would come in handy. I proceeded to the store with the ring and got the ring sent out at no cost due to me having the warranty. A few days went by and we went to pick up the ring after I had to call and ask, I never received a call from them. I then went to the store and my fianc was looking at her ring in details to make sure everything looked perfect. We noticed a big difference in the new diamond that was replaced. The new one is a lot smaller and makes a deep gap in the ring which isnt what right! We then asked for a managers phone number. Speaking with him he gave so much attitude and started to be very disrespectful to me and my fianc in many ways that I didnt think was right of him to do. He accused me of banging my ring into something, he stated that they dont offer a warranty to the customers( but keep in mind, I just got my ring back with a replaced diamond at no additional cost since I had the warranty) now youd think if I didnt have a warranty Id have to pay for this. My fianc is now left with no ring due to the diamond and I need to get my money back. This is ridiculous, the customer service is horrible especially coming from the owner and the lack of understanding. Im beyond upset and now without a ring for my wedding in 3 months, Im in desperate need of a new ring before our big day. I hope you guys can help me out please!