สอบถามวิธีเรียก auto id จากฐานข้อมูล Access มาแสดงบนฟอร์ม vb

Private Sub AutoGenerateMemberID()

        Dim ItemID As String
        Dim s As String = "select MAX( Bill_ID ) FROM Billing "
        Dim dr As OleDbDataReader
        dr = ExecuteReader(s)
        While dr.Read()

            ItemID = "BG" & (CInt(dr(0).ToString().Replace("BG", "")) + 1)
            tb_billingNo.Text = CStr(ItemID)
        End While
        dr.Close()
    End Sub

Private Sub tb_billingNo_TextChanged(sender As Object, e As EventArgs) Handles tb_billingNo.TextChanged
        AutoGenerateMemberID()
    End Sub

Private Sub tb_billingNo_TextChanged(sender As Object, e As EventArgs) Handles tb_billingNo.TextChanged
        AutoGenerateMemberID()
    End Sub

Public Class Form1

    Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
        MessageBox.Show(ReturnID("AA6005-001"))
        MessageBox.Show(ReturnID("AA6006-011"))
    End Sub

    Function ReturnID(strID As String) As String
        'AA6006-001
        Dim s As String = strID.Replace("AA", "") '6006-001
        Dim ss() As String = s.Split("-") '6006,001
        If ss(0).Substring(2, 2) <> Now.Month().ToString("00") Then
            Return "AA" & Now.ToString("yyMM") & "-001"
        Else
            Return "AA" & ss(0) & (CInt(ss(1)) + 1).ToString("-000")
        End If
    End Function
End Class

 Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
        MessageBox.Show(ReturnID("AA6005-001"))
        MessageBox.Show(ReturnID("AA6006-011"))
    End Sub

Private Sub AutoGenerateMemberID()

        Dim ItemID As String
        Dim s As String = "select MAX( ID_Payment) FROM Payment "
        Dim dr As OleDbDataReader
        dr = ExecuteReader(s)
        While dr.Read()

            ItemID = returnID(dr(0).ToString())

            tb_payid.Text = ItemID
        End While
        dr.Close()
    End Sub