The car may not have been used, but...
registered end of July 2024
...you are not the first owner; the dealership that registered the car is. So, in the UK at least, and possibly also in your country, in law you have bought a secondhand car.
In the UK a faulty uniair would be sufficient grounds for rejecting the car.
only if you are the first owner of the car. As far as consumer rights legislation is concerned, a prereg would be treated as a used car, and you'd have to give the seller one chance to repair it.
This does catch some folks out, as you don't quite have the same protections you'd have if you were the first registered owner. For example, the usual insurance protection of being able to get a brand new vehicle if it's written off in the first year doesn't apply to a prereg car. The manufacturers warranty, the service schedule, and the requirement to MOT it will all be based on the date of first registration, not the date you bought it. It also won't be a one owner car when you come to sell it, which could affect its trade in value. There are quite a few good reasons why prereg cars are usually sold at a discount.
All that said, in this case it could be something as simple as a faulty spark plug. I've seen at least one car leave the factory with a cracked insulator; presumably the plug was dropped on the floor during manufacture and just installed. I'll keep my fingers crossed for the OP that something like this is what's happened here.