Changing the date on 2008 navigation

Hi all, I purchased my 2008 Z51 convertible in July of last year. I am still getting to know it. I recently did the firmware update and everything is working fine except I can’t figure out how to change the date on the display of the navigation system. Does anyone know how or if this can be changed?

Just to let you all know. About 3 days after I did the firmware update the date corrected all by itself. I guess it just had to update off the satellite system