Urgent intervention

I tried to checkout and I used a gift voucher and had an outstanding amount of R3 that I authorized to be paid using my debit card. I mistakenly chose the one that I disabled online buying and my purchase was canceled. When I tried to use the gift voucher it says insufficient funds and I don't understand as the first transaction did not go through. When I phoned Woolworth today I was tossed from pillar to post and finally told that the money will only reflect after 7 or 14 working days. My gift card or voucher has an expiry period. I even sent an email that has not been responded to.