STANDARD BANK CHARGES CARD FEES FOR A CARD I DON'T HAVE + REFUSES TO EXPLAIN

I was charged R1,200.00 "card fee" on my current account. I do not have any Standard Bank credit cards. I phoned Customer Services to ask what the charge was for, and they were unable to assist me. Promised to escalate but never did. I made a complaint. Somebody tried to phone me and I emailed him to tell him that I do not have cellphone signal where I am and that he can email me the response in writing. I want to know what the charge of R1,200 was for. He now sent me an email to say that the complaint is Closed, until such time as I provide him with a cellphone no. I want the response by email IN WRITING! not in a phone call. The complaint is not resolved. 10 days later and I do not have answer