Why does an return payment take so long!!!!

i made a payment to the wrong account the 25December, i asked the minuet i sent the payment for it to be recalled a service request number was created, i still up till now even after phoning and emailing standard bank not recieved my money back why...why can the payment just not be revesed ...whats the hold up, then they want to charge me to et my own money back almost R300 its rediculous service and from my personal bank a company i have used and been loyal to for so many years...why do we have to fight to recieve our own money back...whats the hold up, and why can the process not be speed up? why...its not difficult..that money is my sons school fees that i paid incorrectly to my older sons school, school open on monday what do i tell the school that standard bank escalated it....bull...terrible service...its definately time to change banks......they seriously need to work faster this is rediculous a service i am paying for , wel they charging me for to take so long....poor poor customer service!!!!! I am very annoyed!!