querry is returning zero eventhough data is present in data base

 
SqlConnection con = new SqlConnection(strcon);
DateTime dt = Convert.ToDateTime(txtfrom.Text);
string fromDate = dt.ToShortDateString();
DateTime dt1 = Convert.ToDateTime(txtto.Text);
string toDate = dt1.ToShortDateString();
SqlCommand cmdallltransactions = new SqlCommand("select sum(Amount) from AllTransactions where (TransCode <> 0) and (BranchKey = @BranchKey) and ((TransDate > @FromDate )and (TransDate < @ToDate)) GROUP by BranchKey", con);
cmdallltransactions.CommandType = CommandType.Text;
cmdallltransactions.Parameters.Add(new SqlParameter("@BranchKey", Convert.ToInt32(Session["BranchKey"])));
cmdallltransactions.Parameters.Add(new SqlParameter("@FromDate", fromDate));
cmdallltransactions.Parameters.Add(new SqlParameter("@ToDate",toDate));
con.Open();
decimal tot = 0;
tot = Convert.ToDecimal(cmdallltransactions.ExecuteScalar());
txttotal.Text = tot.ToString();
con.Close();