7500 miles average 23.34, mostly highway with cruse on, auto stop is disabled. 87 OCT gas and 33 PSI in the tires. i would check your tire pressure, and if that is not it i would be talking to the dealer.
If u used 2 bottles you used way to much! I have my truck and wife’s car twice on the first bottle including the initial wipe on and off. It only takes 1-2 sprays per quarter panel. U can tell u are using to much if the windows streak when u dry causing you to buff it off for a clear...