what happens when you order from an infomercial online but not all the money is on your card?

I got a $25 Visa Prepaid card & used it for the Wax Vac infomercial online but ordered something extra by accident & there's not enough money on the card. Anybody know what happens, what do they do? Anybody know how I would cancel my order? I looked in FAQ's & the answer's not there. I also emailed them & have not gotten a response. Do they just ignore it & cancel your order or do they bill you?

Simply give them a phone call and explain what happened. I'm sure they can cancel it.