Handed over to attorneys for using a Standard bank product

I have a Standard bank credit card, which sometimes gets used by my family members. Of course they dont know how much credit remains on my card and sometimes exceeds the credit limit. I have a credit limit of R40 000, however Standard bank allows you to go over that limit by about R5000. I received an sms from Standard bank saying I need to repay my exceeded limit or it might affect my credit rating, else my credit card could even get blocked. Not wanting this to happen, I phoned Standard bank and asked them to rather put a hard limit of R40 000 on my credit card so I cant exceed my limit. They said they cannot set a hard limit on my card, however, I dont need to worry as it is part of their product offering and they allow their clients to exceed the limit. They did however say I should try to repay my exceeded limit amount before the end of each month. For this reason every month when I get paid on the 25th, I transfer between R10 000 to R15 000 to my credit card. Suddenly Standard bank handed me over to an attorney, without any prior warning, because of my card that exceeded its limit. What is the point of a limit if that is not the limit? How does Standard bank offer you a product/service, but as soon as you make use of that product or service they hand you over to their attorneys? Does a gym hand their members over to their attorneys after you paid for a membership but enter the gym? Does an airline hand you over to their attorneys after you bought a ticket and get on the plane? Does Makro hand you over to their attorneys after you bought a TV and go home and open the box? No! Because that is the product they offered and the product you paid for! Wake up Standard bank!