Bidorbuy does not want to release my money

I have been selling on bidorbuy a d had no issues.. then there was a bid on a big mac set.. lady won the bet a s eft the money over to them. This was all done.in the 11th of Sept, the money was only available for me to request withdraw.. now they do not want to pay the money over to me.. as I need to buy the set from my supplier I'm order to send it off to the buyer.. but I cant buy it as now bidorbuy does not want to pay that money over to me.. never did they advise me I needed to keep stock on hand. All the other order was exactly the same.. and there was no issues.. it takes 28 working days for the orders to be delivered to the client as the stock gets imported in... so what now.. I am not happy and I need some one to adress this with a matter of urgency