Genesis Mart — genesis mart fraud transaction

I got a call from a number [protected] on 10.10.17 saying that they are calling from visa and master card service provider. I was offered 4 gifts as i have maintained an execellent relation with the credit card for which i had to pay 8420/-. I told them that i wanted to discuss this with my family. But they told that if iam not satisfied with the offer they will reimburse the amount in full. Thus without giving time to think they took me to the ivr process and made me pay 8420/-after an hour when i tried to decline the transaction as my family did not support for this, they clearly denied reimbursing