Bergdorf Goodman / incorrect refund based their own rules which are different from their official website

I waited for half year to get the beauty event which can take you 200 off when you spend 1000. I placed my order through phone call. Then the sales sent me the wrong items and I asked for exchange, but she told me all the options I want were out of stock. I waited for two weeks, then sent wrong items back. They decreased my event gift card because I returned the wrong items. However, I checked with both online chat and phone service, both of them told me I should get back the exact money I paid for everything with the discount price. The Bergdorf Goodman New York store does not follow their rules which other service told me should be the same as stores saying they have different rules. Plus there is no documents and any instructions to prove the different rule she told me. Have no idea what I did wrong? Because I sent back the wrong items??? Worst shopping experience ever have.