Почему этот код не выполняет хранимую процедуру и не вставляет данные?

У меня есть контроллер, указанный здесь, который должен вызывать метод Dapper, однако я не могу заставить его выполниться. Он не выдает никаких исключений и перенаправляется при попытке поймать, однако процедура, похоже, не выполняется, поскольку новые пользователи никогда не создаются.

Настройка соединения работает с помощью простых встроенных методов .Query, однако, как только я пытаюсь сделать это с помощью хранимой процедуры, происходит сбой.

Модель:

    public class User
    {
        public int UserID { get; set; }
        public string Username { get; set; }
        public string Email { get; set; }
        public string Password { get; set; }
        public string FirstName { get; set; }
        public string LastName { get; set; }
        public Boolean ActiveB { get; set; }
    }

Вид:

@model ScaleBase.Models.FullUser

@{
    ViewData["Title"] = "Create";
}

<h2>Create</h2>

<h4>User</h4>
<hr />
<div class = "row">
    <div class = "col-md-4">
        <form asp-action = "Create">
            <div asp-validation-summary = "ModelOnly" class = "text-danger"></div>
            <div class = "form-group">
                <label asp-for = "OrganisationID" class = "control-label"></label>
                <input asp-for = "OrganisationID" class = "form-control" />
                <span asp-validation-for = "OrganisationID" class = "text-danger"></span>
            </div>
            <div class = "form-group">
                <label asp-for = "ClientID" class = "control-label"></label>
                <input asp-for = "ClientID" class = "form-control" />
                <span asp-validation-for = "ClientID" class = "text-danger"></span>
            </div>
            <div class = "form-group">
                <label asp-for = "TeamID" class = "control-label"></label>
                <input asp-for = "TeamID" class = "form-control" />
                <span asp-validation-for = "TeamID" class = "text-danger"></span>
            </div>
            <div class = "form-group">
                <label asp-for = "Email" class = "control-label"></label>
                <input asp-for = "Email" class = "form-control" />
                <span asp-validation-for = "Email" class = "text-danger"></span>
            </div>
            <div class = "form-group">
                <label asp-for = "Username" class = "control-label"></label>
                <input asp-for = "Username" class = "form-control" />
                <span asp-validation-for = "Username" class = "text-danger"></span>
            </div>
            <div class = "form-group">
                <label asp-for = "Password" class = "control-label"></label>
                <input asp-for = "Password" type = "password" class = "form-control" />
                <span asp-validation-for = "Password" class = "text-danger"></span>
            </div>
            <div class = "form-group">
                <label asp-for = "FirstName" class = "control-label"></label>
                <input asp-for = "FirstName" class = "form-control" />
                <span asp-validation-for = "FirstName" class = "text-danger"></span>
            </div>
            <div class = "form-group">
                <label asp-for = "LastName" class = "control-label"></label>
                <input asp-for = "LastName" class = "form-control" />
                <span asp-validation-for = "LastName" class = "text-danger"></span>
            </div>            
            <div class = "form-group">
                <div class = "checkbox">
                    <label>
                        <input asp-for = "ActiveB" /> @Html.DisplayNameFor(model => model.ActiveB)
                    </label>
                </div>
            </div>
            <div class = "form-group">
                <input type = "submit" value = "Create" class = "btn btn-default" />
            </div>
        </form>
    </div>
</div>

Контроллер:

public ActionResult Create(IFormCollection collection)
{
        try
        {
            DynamicParameters parameters = new DynamicParameters();

            parameters.Add("@Organisation", collection["OrganisationID"]);
            parameters.Add("@ClientID1", collection["ClientID"]);
            parameters.Add("@Team", collection["TeamID"]);
            parameters.Add("@Email", collection["Email"]);
            parameters.Add("@UserName", collection["UserName"]);
            parameters.Add("@Password", collection["Password"]);
            parameters.Add("@FirstName", collection["FirstName"]);
            parameters.Add("@LastName", collection["LastName"]);

            var affectedRows = _dapperRepo.CreateUser(parameters);

            return RedirectToAction(nameof(Index));
        }
        catch (Exception)
        {
            throw;
        }
    }

Шикарный репозиторий:

    public async Task<User> CreateUser(DynamicParameters parameters)
    {
        using (IDbConnection conn = Connection)
        {            
            string sproc = "EXEC sproc_NewUser @Organisation, @Client1, @Team, @Email  @UserName, @Password, @FirstName, @LastName";
            conn.Open();
            var result = await conn.QueryAsync(sproc, parameters, commandType: CommandType.StoredProcedure);
            return result.FirstOrDefault();
        }   
    }

Хранимая процедура:

BEGIN TRY 
    BEGIN TRANSACTION NewUser
        DECLARE @salt UNIQUEIDENTIFIER = NEWID()

        INSERT INTO [dbo].[User] (Username, Email, FirstName, LastName, Password, Salt, Active) 
        VALUES (@UserName, @Email, @FirstName, @LastName, HASHBYTES('SHA2_512', @Password+CAST(@salt AS NVARCHAR(36))), @salt, 1)

        INSERT INTO [dbo].[UserOrganisations] (UserID, OrganisationID) 
        VALUES (IDENT_CURRENT('User'), @Organisation)

        INSERT INTO [dbo].[UserClients] (UserID, ClientID) 
        VALUES (IDENT_CURRENT('User'), @Client1)

        IF @Client2 IS NOT NULL
        BEGIN 
            INSERT INTO [dbo].[UserClients] (UserID, ClientID) 
            VALUES (IDENT_CURRENT('User'), @Client2)
        END

        IF @Client3 IS NOT NULL
        BEGIN 
            INSERT INTO [dbo].[UserClients] (UserID, ClientID) 
            VALUES (IDENT_CURRENT('User'), @Client3)
        END

        IF @Client4 IS NOT NULL
        BEGIN 
            INSERT INTO [dbo].[UserClients] (UserID, ClientID) 
            VALUES (IDENT_CURRENT('User'), @Client4)
        END

        IF @Client5 IS NOT NULL
        BEGIN 
            INSERT INTO [dbo].[UserClients] (UserID, ClientID) 
            VALUES (IDENT_CURRENT('User'), @Client5)
        END

        INSERT INTO [dbo].[UserTeams] (UserID, TeamID) 
        VALUES (IDENT_CURRENT('User'), @Team)

        INSERT INTO [dbo].[UserPermission] (UserID, HolidayCount, HolidayUsed, TemplateID, ConfigState1, ConfigState2, ConfigState3, ConfigState4, ConfigState5) 
        VALUES (IDENT_CURRENT('User'), @Holiday, 0, 1, 255, null, null, null, null)

        INSERT INTO [dbo].[UserTime] (UserID, Scale, StartTime, EndTime) 
        VALUES (IDENT_CURRENT('User'), 1, @StartTime, @EndTime)

        COMMIT TRANSACTION NewUser

        PRINT 'Success'

        SELECT 
            [UserID], [Username], [Email], [Firstname], [Lastname], [Active] 
        FROM 
            [User] 
        WHERE 
            [UserID] = IDENT_CURRENT('User')
END TRY
BEGIN CATCH
    IF (@@TRANCOUNT > 0)
    BEGIN
        ROLLBACK TRANSACTION NewUser
        PRINT 'Failed'
    END 

    SELECT
        ERROR_NUMBER() AS ErrorNumber,
        ERROR_SEVERITY() AS ErrorSeverity,
        ERROR_STATE() AS ErrorState,
        ERROR_PROCEDURE() AS ErrorProcedure,
        ERROR_LINE() AS ErrorLine,
        ERROR_MESSAGE() AS ErrorMessage

        RETURN 'Error'
END CATCH