Duplicate Entries in SQL 2005 Server usinb VB.NET

<removed stored="" procedure="">
ALTER PROCEDURE dbo.DuplicateProcParam(@clmnFN nvarchar(200), @clmnPN nvarchar(50), @clmReturnDuplicateValue INT OUTPUT)

AS

    /*DECLARE @rc int */

    SELECT        clmnID, clmnFN, clmnPN, clmnAPN, clmnRB, clmnRP, clmnTA, clmnAsignTo
    FROM            tblAddResume
    WHERE        (clmnFN = @clmnFN) AND (clmnPN = @clmnPN)

    if @@ROWCOUNT=1
        Begin
            SELECT @clmReturnDuplicateValue=1
            RETURN @clmReturnDuplicateValue
        END
    Else
        Begin
            SELECT @clmReturnDuplicateValue=0
            RETURN @clmReturnDuplicateValue
        End

'Checks for Duplicate Users
    Public Function DuplicateProcedure(ByVal FN As String, ByVal PN As String)
        Dim AR As New NSCP.ResumeClass           'Properties

        Dim conn As New SqlConnection()           
        Dim txtValPass As New frmResume
        conn.ConnectionString = strCadenaConexion

        ' AR.propFN = txtValPass.txtFullName.Text
        'AR.propPN = txtValPass.txtPhoneNumber.Text

        Dim cmd As New SqlCommand()
        cmd.Connection = conn
        cmd.CommandType = CommandType.StoredProcedure
        cmd.CommandText = "DuplicateProcParam"



        cmd.Parameters.AddWithValue("@clmnFN", FN)
        cmd.Parameters.AddWithValue("@clmnPN", PN)
        cmd.Parameters("@clmReturnDuplicateValue").Direction = ParameterDirection.Output
        cmd.ExecuteScalar()

        MsgBox(cmd.Parameters.Item("@clmReturnDuplicateValue").Value.ToString)
        cmd.Parameters.Clear()
        ' Create a SqlParameter for each parameter in the stored procedure.
        Dim InsertResumeProcedure As New SqlParameter
        InsertResumeProcedure = cmd.Parameters.Add("@clmReturnDuplicateValue", SqlDbType.Int)
        InsertResumeProcedure.Direction = ParameterDirection.ReturnValue




        Dim previousConnectionState As ConnectionState
        previousConnectionState = conn.State

        Try
            If conn.State = ConnectionState.Closed Then
                conn.Open()

                Dim jj = cmd.Parameters("@clmReturnDuplicateValue").Value

                If jj <> 0 Then
                    'if found show 0 else 1
                    dtrEst = cmdEst.ExecuteReader
                    dtrEst.Read()
                    AR.propID = dtrEst.Item("clmnID")
                    AR.propFN = dtrEst.Item("clmnFN")
                    AR.propPN = dtrEst.Item("clmnPN")
                    AR.propAPN = dtrEst.Item("clmnAPN")
                    AR.propRB = dtrEst.Item("clmnRB")
                    AR.propRP = dtrEst.Item("clmnRP")
                    AR.propTA = dtrEst.Item("clmnTA")
                    AR.propAT = dtrEst.Item("clmnAsignTo")
                End If
            Else
                AR.propID = Nothing
                AR.propFN = Nothing
                AR.propPN = Nothing
                AR.propAPN = Nothing
                AR.propRB = Nothing
                AR.propRP = Nothing
                AR.propTA = 1
                AR.propAT = Nothing
            End If

        Finally
            If previousConnectionState = ConnectionState.Closed Then
                conn.Close()
            End If
        End Try
        Return AR
    End Function

Private Sub btnSaveEditDelete_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnSaveEditDelete.Click
        If Me.btnSaveEditDelete.Text = "Save" Then
            If txtFullName.Text = "" Then
                FullNameErrorProvider.SetError(txtFullName, "Required Field")
            ElseIf txtPhoneNumber.Text = "" Then
                PhoneNumberErrorProvider.SetError(txtPhoneNumber, "Required Field")
            ElseIf txtResumePath.Text = "" Then
                ResumePathErrorProvider.SetError(txtResumePath, "Required Field")
            Else

                '   AR.propFN = txtFullName.Text
                '  AR.propPN = txtPhoneNumber.Text



                objConn.openConexion()
                AR = objConn.DuplicateProcedure(txtFullName.Text, txtPhoneNumber.Text)
                objConn.closeConexion()
                If AR.propFN = txtFullName.Text And AR.propPN = txtPhoneNumber.Text Then
                    If MsgBox("This Applicant is already in the Data Base! Do you wish to Edit the Applicants Information?" & _
                    vbCrLf & "ID: " & AR.propID & vbCrLf & "Full Name: " & AR.propFN & _
                    vbCrLf & "Alt Phone Number: " & AR.propAPN & vbCrLf & "Recommended By: " & AR.propRB & _
                    vbCrLf & "Resume Path: " & AR.propRP & vbCrLf & "Times Applied: " & AR.propTA & _
                    vbCrLf & "Assigned To: " & AR.propAT, MsgBoxStyle.YesNo) = MsgBoxResult.Yes Then
                        Call ENRValues(AR)
                        Me.Close()
                    ElseIf AR.propFN <> txtFullName.Text And AR.propPN <> txtPhoneNumber.Text Then
                        Call ARValueAssignation()
                        objConn.InsertResumeProcedure(AR)
                        MsgBox("The Applicants information was successfully stored.", MsgBoxStyle.Information, "Sucessfull Storage")
                        Me.Dispose()
                    Else
                        MsgBox("Duplicate Entries are not allowed on the Data Base", MsgBoxStyle.Information, "Data Rejection")
                    End If
                Else
                    MsgBox("Store Data")
                End If
            End If
        ElseIf Me.btnSaveEditDelete.Text = "Update" Then

        End If

    End Sub