My code is as follows:
    /**
 * New model file
 */
namespace org.acme.paysystem
enum PaymentStatus{
o PARTIALLY_PAID
o TOTAL_AMOUNT_PAID
o NOT_PAID
}
enum DeliveryStatus{
o DELIVERED
o IN_TRANSIT
}
asset Goods identified by billNo{
  o String billNo
  o Double billAmount
  o DateTime billDate
  o DeliveryStatus deliveryStatus
  o PaymentStatus paymentStatus default = 'NOT_PAID'
}
concept Address{
o String Country optional
o String City optional
o String Street optional
o String Zip optional
}
abstract participant user identified by email{
  o String email
  o String fname
  o String lname
  o Address address
}
participant Retailer extends user {
o String shopNo
o Double amountDue
o Double accountBalance
}
participant Distributor extends user{
o String PAN
o Double bankBalance
}
transaction Payment{
  --> Goods goods
  --> Retailer retailer
  --> Distributor distributor
  o PaymentStatus paymentStatus
}
transaction GoodsMovement {
  --> Goods goods
  o DeliveryStatus deliveryStatus
The script file is as follows:
/**
* @param {org.acme.paysystem.Payment} Payment
* @transaction
*/
function Payment(Payment){
        var paymentRecievedFlag = 0;
        var amountRecieved = 0;
                if(GoodsMovement == 'IN_TRANSIT')
                    {
                         console.log("Goods are IN_TRANSIT");
                    }
          else
          {
            if ((Payment.retailer.accountBalance - Payment.goods.billAmount) > 0 ){
               Payment.retailer.accountbalance -= Payment.goods.billAmount;
               Payment.distributor.bankBalance += Payment.goods.billAmount;
              Payment.paymentStatus = 'TOTAL_AMOUNT_PAID';
              //Payment.goods.paymentStatus = 'TOTAL_AMOUNT_PAID';
          }
            else{
                  Payment.retailer.amountDue = Payment.goods.billAmount - Payment.retailer.accountBalance;
                  Payment.distributor.bankBalance += Payment.retailer.accountBalance;
                  Payment.paymentStatus = PARTIALLY_PAID;
            }}
          return getParticipantRegistry('org.acme.paysystem.Distributor')
               .then(function(distributorRegistry){
                  return distributorRegistry.update(Payment.distributer);
          })
               .then(function(){
                  return getParticipantRegistry('org.acme.paysystem.Retailer');
          })
               .then(function(retailerRegistry){
                  return retailerRegistry.update(Payment.retailer);
          })
                 .then(function(){
                       return getAssetRegistry('org.acme.paysystem.Goods');
          })
                 .then(function(goodsRegistry){
                        return goodsRegistry.update(Payment.goods);
          });       
}
How to solve this error?