Bad service

I bought my opel 2022 grandland x at the dealership. I serviced the vehicle at the same dealership. My opel heard an engine light that kept on popping up. Four times in 3 months I reported this issue but the matter was not resolved. Now the engine light on my vehicle is worse then car is switching off while am driving putting me in danger of getting hit by other cars,then I took it back they say my warranty is finished. All job cards have the same diagnostic errors they day I reported it. I feel it's unfair to me to say my warranty is finished and I should pay meanwhile this issue was reported even before the warranty. How can I get help regarding this issue cause i feel they should sort this out as it falls during the time I reported this. To me the dealership was not fixing the car but clearing of the errors while the damage continued to be major. Now the car needs parts of which this was supposed to be fixed immediately when I brought the car in. Treatment from reception towards this was bad, I asked for solution they tell me to pay. Manager said will handle it but this could have been avoided by them fixing the problem not just clearing errors.