Extremely Irate Customer

I am a first time bidder on bid or buy and was advised by references to the site that the customer is allowed to bid and thereafter pay within 30 days. I bid for a game of 30 seconds with Happy Deals and other essentials from Serenthia, Clearance Corner and Nii. Upon winning I was advised that payment needed to be made within 30 days so I emails all the consumers advising them that payment would be made early on the 29/02/2016 - Monday as this was the last day of the month. All responded and agreed. On Friday i get an SNC from Happy Deals advising that my win has been cancelled and I was extremely unhappy as I had corresponded my method of payment. I immediately contacted Mini (apparent manager) and she was rude and unhelpful and I could not get any further than her as I was still willing to pay for the game. This is extremely ridiculous and I have emails of correspondence as proof. This unhelpful rude and unfriendly approach should not be allowed! I have made payment to all other consumers and all were happy to accept.