Why is the combobox not populating?

Question

SQLite

Hello, I filled combobox with text from the database. It has a table that is filled. Actually, I did everything I found on the forum. But the problem is that it doesn't give combobox info.

private void Combobox1_ContextMenuOpening(object sender, ContextMenuEventArgs e)
        {
            SQLiteConnection conn = new SQLiteConnection("Data Source=C:\\Users\\Степан\\Desktop\\project.db");
            SQLiteCommand command = new SQLiteCommand("select * from Dolznosti", conn);
            conn.Open();
            DbDataReader reader = command.ExecuteReader();
            while (reader.Read())
                Combobox1.Items.Add((string)reader["FIO"]);         //СтолбецТаблицы
            conn.Close();
        }