Bad Service, order date changed without prior notice before checkout and paying!

I placed an order on the 12th of February for delivery for my son's birthday today. Afterwards I received an e-mail confirmation of payment made and delivery but then noticed the date was 16 February and not the 13th of February as initially selected. I then tried to go online and change it but to no avail. I then called the call centre on *** and spoke to Waydene. She told me that unfortunately a date cannot be changed once the order has been placed and the reason was that their system defaulted automatically to the next available date for delivery. She mentioned something about stock and I assumed it is because the contents is out of stock. I asked for the order to be cancelled and be given a refund because it is senseless to have a gift delivered how many days after someone's birthday. I was then told that I am only able to get a voucher to place another order. The lady promised to phone me back with the voucher no but never did. This morning I phoned and the gentleman that took my call immediately told me he will get her to phone me. After an hour or two she called me only to tell me that she has sent a mail to the relevant department regarding the voucher but will go there directly now to follow up. The time is now 10:39AM so how am I supposed to get another voucher, place a new order and still expect delivery today. She promised to phone me back when she called at 9:04AM and no new as yet. I then went online and had a live chat with Ntsako who then informed me the reason for the delivery date is that only Valentine's deliveries gets prioritized, not in so many words but this is essentially what it all comes down to. The more I tried to inquire about my voucher and that time is running out the more I was told about Valentines and the date that was moved. What is going to be done about this? I do not want a voucher, I want a refund in order to use the money towards something else. Order Number ***.