African Bank thievery

I have a loan with African Bank and lost my job last year March after the business closed down. Unemployment insurance was activated for 1 year and recently came to an end. I went to African Bank on the 28th of April to make a payment arrangement for R150 a month which i got an sms proving i would pay R150 from 03/05/2022. On the 30th of April i was debited for R850, a premium i cannot afford and its made me short on my rental payment. On 04/05/2022 i went back to the branch and explained what happened, on the day i was assured that i would recieve a refund in 3 days. I didn't get it. Today 25/05/2022 I went back in to the branch to escalate the matter as i need that money, I was told from head office that the refund is pending investigation and they cannot tell me when i will recieve my money back. Its unfair that i had to spend 3 occasions of unpaid leave to try and get my money back and have to continue begging and borrowing from neighbors until African Bank returns the money they took from my account which wasn't authorized in the first place and now its a problem to return too.