System.NullReferenceException: 'Object variable or With block variable not set.' vb.net

Question

Private Sub updateList(ByVal query As String)
    Dim con As SqlConnection = New SqlConnection("Data Source=DESKTOP-NFIARU8\SQLEXPRESS ; Database = CMS; Integrated Security = True")
    Dim command As SqlCommand = con.CreateCommand()
    con.Open()
    command.CommandText = "SELECT account_id, account_name, account_type FROM account WHERE account_type in (0,1) AND (account_name LIKE @query OR account_phone LIKE @query) ORDER BY account_type"
    command.Parameters.AddWithValue("@query", query + "%")

    Dim reader As SqlDataReader = command.ExecuteReader()

    listBox1.Items.clear()
    While reader.Read
        listBox1.Items.Add(New account(reader.GetInt32(0), reader.GetString(1), reader.GetInt32(2)))


        con.Close()
    End While