2015 Hyundai Santa Fe Sport - driving range drop

When I purchased my vehicle, the driving range said 380. Now when I fill up my gas tank, the driving range is only 330.

The range is based on how much gas you have in the tank and a running average of the mile-per-gallon you are getting. since the tank size didn’t change, your driving must have. Are you doing more driving in the city than you did when new? Did you move? Change jobs? Traffic has gotten worse in 4 years?

New tires for the car that are less efficient can also make a big difference. Have you purchased new tires lately?

Or is the check engine light on?

That is not a NASA type instrument . Check your miles per gallon the old fashioned way . Also you should have a read out of avg MPG . I never get the same miles to empty when I fill up and it usually changes before I have driven a few miles.
How long have you had this vehicle ?