2016 LEXUS ES HYBRID Engine Problems

I HAVE A LEXUS 300 ES HYBRID THAT ADVERTISES 39/40 MPG. I HAVE BEEN GETTING IN THE UPPER 28-31 MPG FOR 2 AND A HALF YEARS NOW .WHEN I FIRST RECEIVED THE VEHICLE IN THE FIRST MONTH I COMPLAINED ABOUT THIS GAS MILEAGE PROBLEM. THEY TOLD ME THE VEHICLE NEEDED TO BREAK IN FOR 500 MILES. AFTER THAT I CONTACTED LEXUS AGAIN, THEY SAID THE CAR NEEDED A 2000 MILE BREAK IN . I KEEP GETTING MORE AND MORE EXCUSES AND THE RUN AROUND. THEN THEY TOLD ME IT WAS MY DRIVING HABIT. I HAVE A CLASS A COMMERCIAL DRIVERS LICENSE AND HAVE BEEN DRIVING BIG RIGS FOR OVER 15 YEARS . I NOW HOW TO DRIVE AND I HAVE A VERY GOOD DRIVING RECORD WITH NO INCIDENTS TO DATE. SO THAT EXCUSE WAS ANOTHER PASS-THE-BUCK ROUTINE FROM LEXUS. I LET THIS GO FOR SUCH A LONG TIME, SINCE I...