Not a Dart Question, Weird 2020 RAM Odometer mileage Question
The truck should also record the engine run time which won’t match the the average MPG may actually show it at 99. Call The corporate number in the back of your owners manual and see what they can do. The other thing is to not worry about the extra 340 miles. My dealer covered a repair after after my truck was out of warranty by 500 or so miles.