Standard Chartered Bank — fraud: standard chartered credit card

I would like to bring to light the over limit fee fraud happening in standard chartered credit cards. If i exceed my credit limit, they should stop me from making the transaction and there should be an intimation on the same. This is the procedure which is followed across all other credit cards i use. With standard chartered credit cards they are following a method of allowing the customer to make the transaction and then enforce a fee for that. This fraud should be questioned by the authorities.