If you think, your Opel has a serious defect that affects the safety of the vehicle, report it to the Opel Dealer immediately. If you’re not happy with how the Opel Dealer is dealing with your report, in the UK you should contact the Driver and Vehicle Standards Agency (DVSA).
But before that, you can describe the fault of your Opel in our forum. Maybe some other Opel owner will learn that he experienced the same issue. Multiple occurrences of identical defects mean a better chance of success in a complaint filed with the DVSA. Our website is visited by Opel owners from all over the world.