Bought a 2017 Honda Accord. That car did not even ...

Bought a 2017 Honda Accord. That car did not even get close to the fuel economy of advertised 27/36 mpg. I drove a Civic and it instantly gave 45 mpg on a highway. I drove Accord for 306 miles and it reported 25.3 mpg economy for that distance. I brought the car back to Tyson's Honda in about 4 days, and said that I don't want it anymore. I was buying it with a fuel economy in mind. I drive on average 80 miles a day, and saving on gas is important to me. Tyson's Honda only agreed to take the car back as a trade in, for several thousand dollars less. People at the dealership were very nice, as any salesman should be. But as far as doing something for customer's satisfaction, nothing was done for me. I'm stuck with a car I don't like.