Worse service from Opel South Africa

I’ve purchased a brand new opel corsa which is 2018 model and had opel got an after market sunroof who they advised was an approved opel dealer. I’ve been having endless problems ever since my purchase of my so called new vehicle. There is a noise coming from the engine , a hair spec in the paint work and my radio goes on and off throughout my whole journey. Should I even add that my smash and grab and bubbles . I honestly regret the purchase of my opel corsa and will never recommend anyone to purchase an opel .ive tried contacting opel South Africa and spoke to pendile who is the supervisor which promised to follow up with the dealer and call me back this was 3 weeks ago and I’m still awaiting her call . I’ve contacting her twice she was unavailable .i spoke to a guy who also promised to call me no later then end of business today and to my surprise I’m still awaiting his call . The service from the head office is highly shocking . I will never recommend anyone to buy an opel vehicle.if I had stayed with my gut I would have never been in this position.