RE:GIFT CARDS

Good Day So last friday i purchased a gift card for R260 at windermere branch, gift card number is ********** 055 and while still in front of the cashier i did my online shopping. Today Friday just been to the store in West Street used the same gift and loaded R300 to do my online shopping. The card says insufficient funds. I then called the call centre and they tell me its takes 24 hours which is absolute bull **** cause last week I did not have an issue. Had the store had the same special on the shoes i would have purchased it from the store. i want this rectified cause now I am sitting with no credit on my gift card to order and also if this item goes out of stock online, who is going to compensate me as this is not my problem.The item i require is 2 pairs of SKU ********** 135030 in size 6. MY NUMBER IS ********** 475.