//Commented so i can start the program. private async static void GetMongoData() { try { var repo = new MongoDbRepository(); var cars = (await repo.GetCarsData()).ToList(); var ctx = new CarsFactoryDbContext(); using (ctx) { foreach (Car car in cars) { if (!ctx.Cars.Any(pl => pl.Id == car.Id)) { ctx.Cars.Add(car); } } ctx.SaveChanges(); } } catch (DataException) { throw new ArgumentException("MongoDb is not set up correctly."); } }