paid twice for the same item

I bought items on the 20th Nov 2019 at Campus squire and I tried paying with my credit card but the machine went offline but on the slip it says the transaction decline due to insufficient funds then I paid using my debit card then it went through but later when checked my online banking App I realized that I paid twice. Went back to the shop and they told me that I have to wait 7 working days no communications then I went back at the shop today and after the manager called account department and they told her that I must wait 7 to 10 days to receive my money. i can't wait for that long, i want my money now