Sterns dnt want to fix my ring

I bought a ring worth 5k at sterns Lakeside mall. I used my credit card and they scanned my ID. The stone fell and I went back. I don't have pop. But I have pop from the bank showing that I purchased at sterns they scanned my ID so clearly they have my record. They refused to fix my ring saying they need pop from sterns. They ladies that work at sterns lakeside mall are so rude