Bad customer service

I ordered from checkers Sixty60 app order number ***5A I was charged an amount of R276.13 for my order. A few minutes after placing the order I was sent a text saying there were 2 products that were out of stock and I should pick and alternative. I did not want an alternative and on the checkers app they readjusted my total amount to R200.15 however I was still authorised the full amount from my bank. I called checkers to raise my concern and I was told it’ll take 10 days for the amount to be refunded. This issue happened before and I never received my refund. I’m extremely disappointed with how checkers deals with refunds when other merchants refund immediately.