I am trying to create a custom workflow within Umbraco forms to allow users to sign up for a mailing list in Newsletter Studio.

The form works and the workflow runs but no information is copied into the mailing list, what am I missing?

using Umbraco.Forms.Core;
using Umbraco.Forms.Core.Enums;
using Umbraco.Forms.Core.Persistence.Dtos;
using NewsletterStudio.Core.Public.Models;

namespace MyFormsExtensions
{

    public class Subscribe : WorkflowType
    {
    public Subscribe()
    {
        Name = "Newsletter Sign-up";
        Id = new Guid("7793f98d-266f-4905-b2f2-9d27438da763");
        Description = "Add sign-ups to the mailing list";
        Icon = "icon-inbox";
    }

    public override WorkflowExecutionStatus Execute(WorkflowExecutionContext context)
    {

            RecordField? recordNewsletteremail = context.Record.GetRecordFieldByAlias("email");
            RecordField? recordName = context.Record.GetRecordFieldByAlias("name");
            RecordField? recordDistrict = context.Record.GetRecordFieldByAlias("district");
            var newsletteremail = recordNewsletteremail.ValuesAsString();
            var name = recordName.ValuesAsString();
            var district = recordDistrict.ValuesAsString();

        var request = AddRecipientRequest.Create(newsletteremail)
            .WithSource("Footer")
            .WithName(name)
           .WithCustomField("District", district)
           .SubscribeTo(Guid.Parse("15C21B14-2673-40E1-9730-ED04B4161DE4"))
            .Build();

        return WorkflowExecutionStatus.Completed;
    }

    public override List<Exception> ValidateSettings()
    {
        return new List<Exception>();


    }
    }
}