dyanamic crystal report

[C# Programming]

hi friends
i am creating crytal report frm the stored procedure ,this works fine when i pass one parameter but it shows an error "incorrect parameter " whn i pass two parameter
my code is
{
ReportDocument reportDocument = new ReportDocument();
ParameterField paramField = new ParameterField();
ParameterFields paramFields = new ParameterFields();
ParameterDiscreteValue paramDiscreteValue = new ParameterDiscreteValue();

paramField.Name = "@Dept";
paramDiscreteValue.Value = TextBox1.Text.ToString();
paramField.CurrentValues.Add(paramDiscreteValue);
paramFields.Add(paramField);

paramField.Name = "@Name";
paramDiscreteValue.Value = TextBox2.Text.ToString();
paramField.CurrentValues.Add(paramDiscreteValue);
paramFields.Add(paramField);

CrystalReportViewer1.ParameterFieldInfo = paramFields;
reportDocument.Load(Server.MapPath("CrystalReport.rpt"));
CrystalReportViewer1.ReportSource = reportDocument;
reportDocument.SetDatabaseLogon("sa", "sa", "OPWFMS-7KYGZ7SB", "test");

}
plz let me knw any chnges