********** sales from Hatfield VW Bryanston

I bought a polo gti from hatfield vw bryanston in January 2018. I was told that the vehicle is a 2018 registered model only to find out later that it is in fact a 2017 model. I requested the manufacturing certificate which clearly states that the vehicle is indeed a 2017 model. Nothing is done to get this ********** sale resolved from either the branch or vwsa. Please assist.