CANNOT GIVE ME A BANK LETTER

I have been with Capitec Bank for the past four years and also even opened an account for my son and have encouraged my family to move to Capitec over the years. i have been using my sons account and wanted a bank letter stating that i am the main signatory of this account (mind you my son is only 5 years old) the lady at Cresta gave me a copy of my contract, i took it with only to be informed that it wasnt what i needed. i went back 6 times only to be given attitude and EVENTUALLY told that they cannot help me. I then went to Fourways where a very nice lady explained to me that Capitec doesnt print letters she would have to call the call centre and they dont know how long it will take. Really, what nonsense is that??? all i want is a bank letter which other banks readily give so are you saying I might get that letter after a month and yet i need it TODAY and have been going to your branches for almost 3 weeks now for the letter (check my records)