I have paid off my used truck through Fifth Third Bank and have the title, so how do I owe the bank 3000?

I have a 2003 Avalanche. I bought it used in 2005. I financed $16k through Fifth Thrid Bank. I was throwing multiple payments to pay this off as quickly as possible. January '06, I made my final bunch of payments, and in Feb '06, I received the title. So last week I was checking my credit report, and it shows that my account with Fifth Third Bank is still open. Not only is it open, I owe $3,000. My question to you is, "How can I still owe the bank after I made all of my payments and title while I have never been notified by Fifth Third that I still owe them?" Thanks in advance!