How do I remove the navigation code from my 2006 Acura TL?

I recently purchased a 2006 Acura TL, and EVERY TIME I start the car I have to put in the 4-digit security code to start up the Navigation. Even If I type the 4-digit code in correctly, it will make me enter it again the next time I get in the car. How do I fix that?|||It might be in valet mode or something. Read your manual and find out.