public async Task AddCustomerToTripAsync(Guid tripId, Guid customerId)
        {
            var trip = await _tripRepository.GetTripAsync(tripId);

            if (trip.TripStatus == TripStatus.Cancelled)
            {
                throw new DomainException(DomainErrorCodes.AddingCustomerToCancelledTrip, null,
                                          "Cannot add customer to cancelled trip");
            }

            var customer = await _customerRepository.GetCustomerAsync(customerId);

            CheckTripNullOrFail(trip);
            if (customer == null)
            {
                throw new DomainException(DomainErrorCodes.CustomerDoesNotExist, null, "Customer does not exist!");
            }

            await _tripRepository.AddCustomerToTripAsync(trip, customer);
        }