Got exactly the same, this has to be a sick joke or a huge mistake. I have over 5k on hold and had a huge increase in my traffic last month. I also have several downloads and one registration this month. The funny thing is I got an e-mail from the account manager saying they were happy with the traffic, and then the accounting department comes along and sends this crap!!
In an industry where you are dead if you break trust, they are certainly on very dangerous ground. I hope to have this sorted out tomorrow before noon.