Refund taking up to 10 days!!

On Sunday 2017-12-10, I made a purchase at Pep Home in ********** There was a time-out on the machine when my card was swiped. The transaction went through twice on my bank account. I was assured by the cashier that it will automatically be reversed on the same day. On Monday 2017-12-11, I phoned my bank (FNB) to enquire as the transaction was never reversed. The lady informed me that it would take 5-7 working days for the bank to reverse the transaction, but advised me to rather go to the store where I made the purchase and ask them to call the merchant to reverse the transaction as it would be much quicker. On Tuesday 2017-12-12, I took time off from work to go to the store. I explained what happened to Thando, who tried to help me by calling the finance department. She then told me that it would take about 10 working days to reverse. This is absolutely unacceptable, as this was no fault on my side. It is a big amount (R1324.87) and is part of my living costs for December. I am very disappointed in this store and want my money back before Christmas!