overcharged by chashier

The cashier mistakenly overcharged me by R999.99. <br> When i was making the payment i thought the total was a bit high. And as i left i rechecked the till slip. Only to discover i was correct. I returned immediately and revealed to the the cashier her mistake. She apologised and said she 'forgot' to remove it. I was very understanding and waited for assistance from her supervisors. They returned and asked me if cash would be acceptable. I said that was fine. Then i waited longer and then supervisors told me now they will refund my card. Thandiwe then did the process. And i checked my account. Only the money is not reflecting. She told me dont worry it will reflect. Today is sunday and the money is still not reflecting. I love shopping there by now i have a concern of returning as i may have this happen again. Also when is my money going to reflect. R999.99 is allot of money for me. Can you please help?