I was ****** day light by a cashier

I should be giving it a 0, because tell me why I asked for R1400 cash back but the cashier decided to do R2400 and he only gave me R1400 I only realized when I got home when I went through my notifications and slip. I went back to the store this morning asked for the manager to assist and they went through the footage and saw the transaction and indeed it shows that I was given R1400, now why am I not being refunded my money immediately instead I'm told to go back home they will call me back until the guy that took my money arrives to work