Do not deliver on service

I wanted to make a payment for a British airways ticket on Tuesday 14 July. My card was declined. I thought impossible but gave them my credit card details instead. The following day a receive a automated voice call from FNB regarding the ********** transaction to British airways. The call states press 1 to cancel the transaction or press 2 to allow the transaction. I have now already paid with my credit card. So I press 1 to cancel. The voice then states I must hold to speak to a consultant or press 5 for one to phone me back. I press 5. I have yet to receive a phone call from one of FNB's consultants! Today, 16 July, I receive an sms from FNB stating the payment for FNB on my debit card has now gone off. Which means I have paid for the ticket twice! I am extremely annoyed to say the least. How dare they decline a transaction and then 2 days later allow for it to go through? What the hell??? Why can't they get hold of the customer who's account it is before making their won decisions? Disgusted with how FNB operate!