checkoutReview method Null safety

Future<CheckoutReviewModel> checkoutReview(
  1. {required int customerId,
  2. int? paymentOptionId,
  3. int? addressId,
  4. int? loyaltyPoints,
  5. int? pickStoreID}
)

It's used to get final stage in checkout cycle, It's just a review contains order Items - selected payment - selected address

Implementation

Future<CheckoutReviewModel> checkoutReview(
    {required int customerId,
    int? paymentOptionId,
    int? addressId,
    int? loyaltyPoints,
    int? pickStoreID});