Cannot buy apps in Play Store

I recently made an Android Application for a company and today they ordered 10 tablets (Samsung Galaxy Tab 2 3G GT-P5100) with my application. I created a Gmail Account for each Tablet and updated the software and I bought the first copy of my app with a credit card (it was succesfull and everything went perfect). When I tried to buy another copy of my app with the second Tablet I get this error: I tested all my 8 Tablets, used another Credit Card, another internet connection (3G) but I wasn't able to buy my own application! I even tried to buy Fruit Ninja and I still get the same error. The error is in dutch, this is the translated version: > A technical problem occurs. > > We can not complete the purchase process because of a technical > problem. > > Details of the problem: > > We cannot process this request. Any charges will automaticly be > canceled in 24 hours. Try it again in 24 hours I am very confused, I recently bought a few apps for my own. I think it's because I used the same credit card for multiple Google Checkout Accounts but I don't think that's the only problem (I tried another credit card). I even called my Credit Card company and they said Google didn't even charged me when the transaction failed so the problem cannot be my Credit Card.