Nunit and Mocking in c# with database

I have a method which uses IQueryable to get the value from another class, when I try to mock it normally and my expected result is always "System.Threading.Tasks.Task`1[Nop.Core.Domain.OnTrack.Road]" in Nunit. Can someone help me in resolving this issue?

Implementation Class:

    public async Task<Track> OnTrack(int warId, int cardno, string trackName)
    {
        trackName = GetAssignedtrackName(trackName, cardno);
        Track track;

        using (var scope = TransactionScopeExtensions.AsyncScope())
        {
            track = await (from s in _trackRepository.Table
                where s.Name == trackName && s.warId == warId
                select s).FirstOrDefaultAsync();

            if (track != null && track.CarVariantId.HasValue)
            {
                throw new ErrorCodeException(trackAssignmentErrorCode.AlreadyAssigned);
            }

            // Get car variant ID
            var carVariantId =
                (from cv in _carVariantRepository.Table
                 join c in _carRepository.Table on cv.CarId equals c.Id
                 where !c.Deleted && !cv.Deleted && c.Id == cardno
                 orderby cv.Published descending
                 select cv.Id).FirstOrDefault();

            if (carVariantId == 0)
            {
                throw new ErrorCodeException(CatalogErrorCode.CarVariantNotFound);
            }

            if (track != null)
            {
                track.CarVariantId = carVariantId;
                await _trackRepository.UpdateAsync(track);
            }
            else
            {
                track = new track
                {
                    Name = trackName,
                    CarVariantId = carVariantId,
                    Quantity = 0,
                    warId = warId
                };
                await _trackRepository.InsertAsync(track);
            }

            scope.Complete();
        }

        return track;
    }

Repository Code:

  public partial interface IRepository<T> where T : BaseEntity
    {
        T GetById(object id);
        Task<T> GetByIdAsync(object id);
        void Insert(T entity, bool saveChanges = true);
        Task InsertAsync(T entity, bool saveChanges = true);
        void InsertRange(IEnumerable<T> entity, bool saveChanges = true);
        Task InsertRangeAsync(IEnumerable<T> entity, bool saveChanges = true);
        void Update(T entity, bool saveChanges = true);
        Task UpdateAsync(T entity, bool saveChanges = true);
        void Delete(T entity, bool saveChanges = true);
        Task DeleteAsync(T entity, bool saveChanges = true);
        int SaveChanges();
        Task<int> SaveChangesAsync();
        IQueryable<T> Table { get; }
        void AttachAndUpdateProperty<TProperty>(T entity, params Expression<Func<T, TProperty>>[] modifiedProperties);
    }
}

And my test Code looks like this:

IRepository<Track> _itrackRepository;
        IRepository<Car> _icarRepository;
        IRepository<CarVariant> _icarvariantRepository;
        ITrackService _trackService;
        Car _car1, _car2;
        CarVariant _carvar1, _carvar2;
        Track _track1, _track2;

        [SetUp] // has all the mockup data
        public void setup()
        {
            _track1 = new Track()
            {
                Id = 123,
                Name = "PER123",
                Quantity = 1,
                CarVariantId = 123,
                QuantityOnHold = 1,
                WarId = 123,

            };
            _track2 = new Track()
            {
                Id = 11,
                Name = "PER11",
                Quantity = 1,
                CarVariantId = 11,

            };
            _car1 = new Car()
            { Id = 123, Deleted = false, Name = "PER" };
            _car2 = new Car()
            { Id = 11, Deleted = false, Name = "PER" };
            _carvar1 = new CarVariant()
            {
                Name = "PER123",
                Id = 123,
                Deleted = false,

            };
            _carvar2 = new CarVariant()
            {
                Name = "PER11",
                Id = 11,
                Deleted = false
            };




            _itrackRepository=MockRepository.GenerateMock<IRepository<Track>>();
_itrackRepository.Expect(x => x.Table).Return(new List<Track>() { _track1, _track2 }.AsQueryable());
            _icarRepository = MockRepository.GenerateMock<IRepository<Car>>();
            _icarRepository.Expect(x => x.Table).Return(new List<Car>() { _car1, _car2 }.AsQueryable());
            _icarvariantRepository = MockRepository.GenerateMock<IRepository<CarVariant>>();
            _icarvariantRepository.Expect(x => x.Table).Return(new List<CarVariant>() { _carvar1, _carvar2 }.AsQueryable());
            _trackService = new TrackService(_itrackRepository, _icarvariantRepository, _icarRepository);
        }

    [Test]
    public async Task AssignTrack_test0001()
    {
        var temp = await (_trackService.OnTrack(321, 321, "fre"));

        AreEqual("PER123", temp);
    }