ทำไมผมบันทึกข้อมูลลงใน db access แล้วพอเปิด db ไม่มีข้อมูลอะไรเลย

 Dim stru As String = TextBox1.Text
        Dim strp As String = TextBox2.Text
        Dim objconnection As OleDbConnection = Nothing
        Dim objcmd As OleDbCommand = Nothing
        Dim strSQL As String
        Dim dbconn As OleDbConnection = Nothing
        dbconn = New OleDbConnection("Provider=Microsoft.ACE.OLEDB.12.0;Data Source=D:\database\Database4.accdb;")
        dbconn.Open()
        strSQL = "insert into Member1 (username,[password]) values (?,?)"
        objcmd = New OleDbCommand(strSQL, dbconn)
        objcmd.Parameters.Add(New System.Data.OleDb.OleDbParameter("username", stru))
        objcmd.Parameters.Add(New System.Data.OleDb.OleDbParameter("password", strp))
        dbconn.Close()
        MsgBox("ok")