Wrong Engine fitted into my vehicle!!!!

I purchased a Opel Corsa OPC Nurburgring edition about 1 year ago and ran into some trouble with the vehicle in October 2015, Took the vehicle to Williams Hunt Durban to Diagnose the problem and turns out one of my pistons had low compression.<br> <br> General Motors had authorised a motor change in the vehicle under warranty and the engine was replaced. However on picking up the vehicle and running the engine in I found that the vehicle was under powered, I had it dyno tested and turns out the new engine is 30kw less powerful than the previous engine! I took the car back to Williams Hunt and guess what! The wrong engine had been put into my vehicle!!! GM factory had supp**** the wrong engine and the dealership had not picked up that what was supp**** was wrong!!! I think this is absolutely shocking on the part of General Motors and will definitely be taking this issue further. <br> <br> I have been driving a vehicle with the wrong engine for 4 months and I had to self diagnose my issues because I have had no assistance from GM or the dealership! Customer service is shocking! Service delivery is shocking and General Motors seems to think the issue of putting the wrong engine in my car is minor!