Bought 3 2liters on Friday from my local grocier. Opened one Monday this week, And it was Flat! Opened another on Wen. It was flat too! One left but it will go down the drain with the others!!! Proof of Purchase # on one is ...2010-0041 2L and...4900005013. They are also costing too much! 2 for 3 $ is crazy. But I love diet coke so I bought it. But to pay that only to get a aweful flat product is not fair to any consumer!!!1