Low fuel alert at 20 miles driving range only - can it be changed?

[GDada]

Hi -

We have a new nh300. The yellow light and low fuel alert come up only when the car has about half a gallon left (20 miles driving range with an average 34mpg), which is too low for us, especially when driving in Texas. Can the car be configured to set the alert when there is more gas on the tank? Or is there something wrong with our car? (it only takes 12 gallons when refilling right as the light comes up).

Thanks in advance