Feels like ***** by Standard bank! Credit card account meant to be closed but there is still activity happening on the account by Standard ban****!!!

In October 2019 I settled my credit card bill and closed the account. I received an email to confirm the account has been closed. In December I see online that they are still adding charges to the account in November and December so I logged a complaint. I then started receiving calls every single day with the same thing, asking me if I know what the transactions are on my account! Each time I said that I have already complained that they are still adding charges onto my account when it is meant to be closed. Each time I get an apology and they say that the account is closed, it's the system that is automatically still adding the charges because the statement date has already run??? and they see in the notes that it is all meant to be reversed on the 27th Dec '19. Well it hasn't been reversed and I am still being harassed with the same calls still and every time now I say I am not giving my ID number again because you guys are calling for the same thing every time and you are not sorting out the problem. I have now got an automative call saying I am overdue on my credit card! Now I check and they have added more charges on the 2 Jan 2020! Why am I informed that my credit card is cancelled/closed but then Standard bank continue to have activity on the account by issuing charges etc and I would not have known this if I wasn't able to still see the account on my internet banking. Feels like ***** by Standard bank to me.