Dulux paint a ******** the public

I bought 4 20lt dulux 12 weather guard about a year ago the exact date was the 25 August 2018 to my surprise after 1 year the extior wall has started flaking and is now peeling, I however used plaster primer before painting as instructed by the dulux team at dulux jacobs in Durban but still my wall flaked an started peeling, please advice on the way forward as I would like a refund on this paint. At it was purchased at dulux jacobs. Im shocked because dulux is supposed to be the best im highly disappointed