How do I reject my new Land Rover Discovery Sport based on misleading claims about mpg?

I recently bought a Land Rover Discovery Sport 150 E because it was advertised as having better fuel consumption than previous generation Land Rover. However, I only get 40 mpg over the first 1500 miles which is less than my part exchanged Land Rover Freelander. Have you any guidance on how to reject the car based on misleading claims about better mpg?

Asked on 1 March 2017 by Leonard Shepherd

Answered by Honest John
These are not "misleading claims". They are the results of the prescribed NEDC lab tests that Land Rover is compelled to make by EC law. Real mpg for the Discovery Sport here:
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