How to delete datagridview data with date column time C#

private void butDelete_Click(object sender, EventArgs e)
    {
    if (MyDataGridView.DataSource is DataTable dt)
        {
        List<int> deleteThese = new List<int>();
        DateTime remove = new DateTime(2019, 2, 7);
        int index = 0;
        foreach (DataRow row in dt.Rows)
            {
            if (row["Appointment"] is DateTime apt && apt == remove)
                {
                deleteThese.Add(index);
                }
            index++;
            }
        foreach (int i in deleteThese)
            {
            dt.Rows[i].Delete();
            }
        }
    }