public void WhenName_IsNotUniqueForBooking_ShouldReturnFalse() { _bookingRepoMock.Setup(x => x.GetBookingByMeetUpIdAsync(It.IsAny <int>())).ReturnsAsync( new List <Booking>() { new Booking() { Name = "User1" } }); var bookingService = new BookingService(_bookingRepoMock.Object); var result = bookingService.CkeckNameIsUniqueAsync("User1", 1).Result; result.Should().Be(false); }