Makro Online

I did my online purchase on Thursday 23rd November 2017. I received my Online Order number as well as "Payment successful" on my order which I have printed as a precaution. I then followed up with Makro on my order, only to be told that my order is not valid as payment was not done. Clearly this was a problem on their side with their payment system. I am willing to pay again but im told that I cannot be given the same prices. I feel this is totally unfair, as I was issued a order number and was under the impression that my order was successful. Thanks Thesh