I'm trying to set shipping methods through initialization and don't see why I'm getting this ForeignKeyConstraint exception. 

ForeignKeyConstraint FK_ShippingOption_ShippingMethod requires the child key values (18ede71f-3df3-4d9e-a4cb-3d25881c1ec6) to exist in the parent table

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using EPiServer.DataAbstraction;
using EPiServer.Framework;
using EPiServer.Framework.Initialization;
using EPiServer.Logging;
using EPiServer.ServiceLocation;
using Mediachase.Commerce;
using Mediachase.Commerce.Orders.Dto;
using Mediachase.Commerce.Orders.Managers;
using Mediachase.Commerce.Plugins.Shipping.Generic;

namespace Business.Initialization
{
    [InitializableModule]
    public class ShippingMethodIntialization : IInitializableModule
    {
        private readonly ILogger _logger = LogManager.GetLogger();
        private readonly Injected _currentMarket = default(Injected);

        public void Initialize(InitializationEngine context)
        {

            var currentMarketId = _currentMarket.Service.GetCurrentMarket().MarketId.Value.ToString();

            var shippingMethod = ShippingManager.GetShippingMethods("en");

//this is the shippingMethodOptionId -> 18ede71f-3df3-4d9e-a4cb-3d25881c1ec6
            var shippingMethodOptionId = shippingMethod.ShippingOption[0].ShippingOptionId;


            var shippingMethodInfo = new List
            {
                new ShippingMethodInfo("ShippingMethodTest", "ShippingMethodTest name", "ShippingMethodTest description", "USD", 100, 1, false, shippingMethodOptionId)

            };

            CreateForEnabledLanguages(shippingMethodInfo);

        }

        public void Uninitialize(InitializationEngine context)
        {

        }

        private void Create(ShippingMethodInfo shippingMethodInfo, Guid guid, string languageId)
        {
            ShippingMethodDto shippingMethod = new ShippingMethodDto();
            ShippingMethodDto.ShippingMethodRow shippingMethodRow = shippingMethod.ShippingMethod.NewShippingMethodRow();

            shippingMethodRow[shippingMethod.ShippingMethod.ShippingMethodIdColumn] = guid;
            shippingMethodRow[shippingMethod.ShippingMethod.LanguageIdColumn] = languageId;
            shippingMethodRow[shippingMethod.ShippingMethod.NameColumn] = shippingMethodInfo.Name;
            shippingMethodRow[shippingMethod.ShippingMethod.DisplayNameColumn] = shippingMethodInfo.DisplayName;
            shippingMethodRow[shippingMethod.ShippingMethod.DescriptionColumn] = shippingMethodInfo.Description;
            shippingMethodRow[shippingMethod.ShippingMethod.CurrencyColumn] = shippingMethodInfo.Currency;
            shippingMethodRow[shippingMethod.ShippingMethod.BasePriceColumn] = shippingMethodInfo.BasePrice;
            shippingMethodRow[shippingMethod.ShippingMethod.ShippingOptionIdColumn] = shippingMethodInfo.ShippingOptionIdColumn;
            shippingMethodRow[shippingMethod.ShippingMethod.IsActiveColumn] = true;
            shippingMethodRow[shippingMethod.ShippingMethod.IsDefaultColumn] = true;
            shippingMethodRow[shippingMethod.ShippingMethod.OrderingColumn] = shippingMethodInfo.Ordering;
            shippingMethodRow[shippingMethod.ShippingMethod.CreatedColumn] = FrameworkContext.Current.CurrentDateTime;
            shippingMethodRow[shippingMethod.ShippingMethod.ModifiedColumn] = FrameworkContext.Current.CurrentDateTime;


            shippingMethod.ShippingMethod.Rows.Add(shippingMethodRow);
           

            ShippingManager.SaveShipping(shippingMethod);
        }

        private void CreateForEnabledLanguages(List shippingMethodInfos)
        {
            var enabledSiteLanguages = GetEnabledSiteLanguages();
            foreach (var enabledSiteLanguage in enabledSiteLanguages)
            {
                var shippingMethodsForLanguage = GetShippingMethodsForLanguage(enabledSiteLanguage.LanguageID);

                foreach (ShippingMethodInfo shippingMethodInfo in shippingMethodInfos)
                {
                    if (shippingMethodsForLanguage.Exists(p => p.Name == shippingMethodInfo.Name))
                        continue;

                    try
                    {
                        Guid shippingMethodId = GenerateShippingMethodId();
                        Create(shippingMethodInfo, shippingMethodId, enabledSiteLanguage.LanguageID);
                    }
                    catch (Exception e)
                    {
                        _logger.Error("Could not create shipping method. See next log item for more information.", e);
                        _logger.Error($"Could not create payment method with name: {shippingMethodInfo.DisplayName} for language:{enabledSiteLanguage.LanguageID} during initialization");
                    }
                }
            }
        }

        private List GetShippingMethodsForLanguage(string languageId)
        {
            return ShippingManager.GetShippingMethods(languageId, true).ShippingMethod.ToList();
        }

        private IEnumerable GetEnabledSiteLanguages()
        {
            var languageBranchRepository = ServiceLocator.Current.GetInstance();
            return languageBranchRepository.ListEnabled();
        }

        private Guid GenerateShippingMethodId()
        {
            var id = Guid.NewGuid();
            while (ShippingManager.GetShippingMethod(id, true).ShippingMethod.Count > 0)
            {
                id = Guid.NewGuid();
            }
            return id;
        }

        private class ShippingMethodInfo
        {
            public string Name { get; set; }
            public string DisplayName { get; set; }
            public string Description { get; set; }
            public string Currency { get; set; }
            public decimal BasePrice { get; set; }
            public int Ordering { get; set; }
            public bool IsDefault { get; set; }
            public Guid ShippingOptionIdColumn { get; set; }

            public ShippingMethodInfo(
             string name,
             string displayName,
             string description,
             string currency,
             decimal basePrice,
             int ordering,
             bool isDefault,
             Guid shippingOptionIdColumn)
            {
                Name = name;
                DisplayName = displayName;
                Description = description;
                Currency = currency;
                BasePrice = basePrice;
                Ordering = ordering;
                IsDefault = isDefault;
                ShippingOptionIdColumn = shippingOptionIdColumn;
            }
        }
    }
}