Empire Service Station

After buying my gas there for over a year, there is an issue with the last tank of gas pumped for me. I should have filled the tank with 9 gallons, but the pump registered that it pumped 14.25 gallons. The tank only holds 14.9 gallons. My mpg went from 26 mpg to 18 mpg in less than a week and there was no difference in driving conditions. I wont be going back there.