Standard bank HL charging me with things I did not sign up for, and STDBNK cannot explain.

I have a bad experience with Standard bank, I have been in contact with them several times and seems not going anywhere. I was charged with R1000 when I enquire about this no one seems to understand what this was for, I was told to fami****ize myself with my contract cause it there, I did that and there was nothing, wrote to them again last week, someone called me on Monday 29/01/24 around 15h00,however again did not know why and what was the charge for. I requested them to write a report of what was discussed unfortunately that did not happen. I believe that STDBank has been overcharging me for things I did not sign up for.