Value doesnot show in datagridview

DateTime startT = new DateTime();

DateTime endT = new DateTime();

startT = dateTimePicker1.Value.Date;

endT = dateTimePicker2.Value.Date;

if (startT.Date > endT.Date)

{

MessageBox.Show("To Date Cannot be greater than Start Date");

}

else

{

string connetionString = null;

connetionString = ConfigurationManager.ConnectionStrings["AccessConnectionString"].ConnectionString;

con.ConnectionString = connetionString;

DataSet ds = new DataSet();

string sql = "SELECT Medicine_name,sum(Medicine_count) as Medicine_count,To_Date from Medicine_count_info where [To_Date] Between #" + startT.ToString("dd'/'MM'/'yyyy") + "#And #" + endT.ToString("dd'/'MM'/'yyyy") + "#group by Medicine_name,Medicine_count,To_Date order by Medicine_count desc ";

OleDbConnection connection = new OleDbConnection(connetionString);

OleDbDataAdapter dataadapter = new OleDbDataAdapter(sql, connection);

ds = new DataSet();

connection.Open();

dataadapter.Fill(ds);

connection.Close();

dataGridView1.DataSource = ds;

dataGridView1.DataMember = ds.Tables[0].TableName;

dataGridView1.Refresh();

}