Sbccreditcardo Mumbai In — Discount Card which was supposed to provide me discount @25% on every purchase

On 8/11/2021 some Shweta Gupta called me from "SBI Card". She told me that SBI Credit Card is discontinuing reward system and introducing discount card which, on being produced at the time of billing, will give me discount @25% on every purchase. I was not willing to take such card, but at that time I was in hurry and with constant persuasion she convinced me and asked my CVV, DOB, Last few digits of the card number one by one. I refused to give those information first, but then again I told her everything. Then her senior, as Shweta suggested, called me for confirmation and then only I came to know that I have to make payment for that card. This time I vehemently denied to pay Rs 8578.00 for that card . He agreed and told me that he would forward the cancellation request . Then he took an OTP from me to process the cancellation request. He gave me his number for future communication. When I found that the above-mentioned amount was being shown in the unbilled transaction of my SBI Credit Card, I tried to contact him and found the mobile switched off. Now SBI Credit Card bill dated 7/12/21 has included the said amount, but I have not received any card. I have no document of this purchase. There is no customer care no of SBI Credit Card where I can lodge complaint. I wrote to them, but they are always asking for documents which I don't have. Can you help me?