ทำปุ่ม update ข้อมูลใน SQL แล้วขึ้น error ตามรูปคับ

Imports System.Data.SqlClient

Public Class frmmember
    Dim cn As New SqlConnection("Server=localhost;Initial Catalog=Cookies;Integrated Security=SSPI")
    Dim cmd As New SqlCommand
    Dim da As New SqlDataAdapter
    Dim dt As New DataTable

    Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
        Dim i As Short
        cn.Open()
        Using cmd As New SqlClient.SqlCommand("INSERT INTO Member(Mem_name,Mem_last,Mem_birth,Mem_add,Mem_email,Mem_tel) values('" & TextBox2.Text & "','" & TextBox3.Text & "','" & Format(DateTimePicker1.Value, "MM/dd/yyyy") & "','" & TextBox4.Text & "','" & TextBox5.Text & "','" & TextBox6.Text & "')", cn)
            i = cmd.ExecuteNonQuery()
        End Using
        cn.Close()
        If (i > 0) Then
            MessageBox.Show("Success Save Data")
            showdata()
        End If
    End Sub
    Private Sub showdata()
        DataGridView1.RowTemplate.Height = 50
        cn.Open()
        With cmd
            .Connection = cn
            .CommandText = "select * from Member"
        End With
        da.SelectCommand = cmd
        dt.Clear()
        da.Fill(dt)
        DataGridView1.DataSource = dt
        cn.Close()
        DataGridView1.Columns(4).Width = 130
        For i As Integer = 0 To DataGridView1.Columns.Count - 1
            If TypeOf DataGridView1.Columns(i) Is DataGridViewImageColumn Then
                DirectCast(DataGridView1.Columns(i), DataGridViewImageColumn).ImageLayout = DataGridViewImageCellLayout.Stretch
            End If
        Next
        cn.Close()
    End Sub

    Private Sub frmmember_Load(sender As Object, e As EventArgs) Handles MyBase.Load
        showdata()
    End Sub

    Private Sub Button4_Click(sender As Object, e As EventArgs) Handles Button4.Click
        Me.Hide()
    End Sub

    Private Sub DataGridView1_CellClick(sender As Object, e As DataGridViewCellEventArgs) Handles DataGridView1.CellClick
        TextBox2.Text = DataGridView1.Item(1, e.RowIndex).Value
        TextBox3.Text = DataGridView1.Item(2, e.RowIndex).Value
        DateTimePicker1.Text = DataGridView1.Item(3, e.RowIndex).Value
        TextBox4.Text = DataGridView1.Item(4, e.RowIndex).Value
        TextBox5.Text = DataGridView1.Item(5, e.RowIndex).Value
        TextBox6.Text = DataGridView1.Item(6, e.RowIndex).Value
    End Sub

    Private Sub Button2_Click(sender As Object, e As EventArgs) Handles Button2.Click
        Dim i As Short
        cn.Open()
        Using cmd As New SqlClient.SqlCommand("Update Member set Mem_name = '" & TextBox2.Text & "',Mem_last = '" & TextBox3.Text & "', Mem_birth'" & DateTimePicker1.Text & "',Mem_add = '" & TextBox4.Text & "', Mem_email = '" & TextBox5.Text & "',Mem_tel = '" & TextBox6.Text & "' where Mem_id = " & DataGridView1.SelectedRows(0).Cells(0).Value & "", cn)

            i = cmd.ExecuteNonQuery()
        End Using
        cn.Close()
        If (i > 0) Then
            MessageBox.Show("Update Data Success")
            showdata()
        End If
    End Sub

    Private Sub Button5_Click(sender As Object, e As EventArgs) Handles Button5.Click
        Dim i As Short
        cn.Open()
        With cmd
            .Connection = cn
            .CommandText = "delete from Member Where Mem_id = " & DataGridView1.SelectedRows(0).Cells(0).Value
            i = .ExecuteNonQuery()
        End With
        If (i > 0) Then
            MsgBox("Delete Success")
        End If
        cn.Close()
        showdata()
    End Sub
End Class