I know this is a week old, but I'm having this same problem. I sent an email to Case Labs before finding this, but I'll reply here anyway.
I've tried chrome, firefox, and internet explorer, all three of them in their latest versions, and on two different computers, and get this same notification every time. Has anybody else been able to successfully order in the past week or two, if so, what did you use to do it?
Edit: I managed to get it through on my phone, case labs said an email confirmation was sent to my email (And gave me the correct email) and the order is marked as complete, but I didn't get an email from caselabs at all, only from paypal saying I spent money.
Edit (Again): Everything has been cleared. Got my gift certificate with my credit so I could apply it and buy my M10 with a debit lol... Case has been ordered and I'm awaiting my last confirmation now. Even though I didn't get help from here, thanks anyway! lol.
Edited by xIHexIx - 4/17/13 at 7:23pm