Audi quality joke

Hey guys…. I am having a nightmare with my Audi A6 2019 which I don’t even have 1 year. I was driving a long and my car staring to lose power. A Drive system fault came on and the car no longer starts. Audi did a diagnosis on it and nothing was showing up?? They could not tell me what was wrong with car they said they would need more time to investigate further. Two weeks later I have been hit with an estimated bill on what needs to be done. The whole fuel system needs replacing with parts and labour time totally €13,000 How does this happen to an Audi A6 2019 car??