Refund on account

I have made an over payment on my account which i was not aware of , but when i received my account statement i saw that i have over paid vir R1440. I have contacted the company via email since march and i kept on getting a response of my money being refunded in 5 to 7 working days. I even contacted them on several occassions which the last was yesterday 2021.05.17. I left my number so the manager can call me back, but still i am waiting. I just want to know how long does it take to process a refund when you have my bankstatement and all questions were answered. A response will be much appreciated.