My update function not working

When I click "View", data from Database populates the form. I click on a field, make changes, click "Update". Update not working. No error! Where is my problem?

Button View

try
{
conn.Open();
index = 0;
//showData(index);
var query = "select * FROM Questions"; //WHERE AuthorizationCode='" + txtauthorizationcode.Text + "'
var cmd = new SqlCommand(query, conn);
SqlDataReader dr = cmd.ExecuteReader();
var sSingle = "Single Choice";
var sMultiple = "Multiple Choice";
while (dr.Read())
{
if (dr.GetString(9) == sSingle)
{
grpmultipleanswers.Visible = false;
grpsingleanswers.Visible = true;
txtquestion.Text = dr.GetString(2);
//txtquestion.Text = dr.GetValue(2).ToString();
txta.Text = dr.GetString(3);
txtb.Text = dr.GetString(4);
txtc.Text = dr.GetString(5);
txtd.Text = dr.GetString(6);
cmbqtype.SelectedItem = dr.GetString(9);
cmbcomplexity.SelectedItem = dr.GetString(10);
lblscore.Text = dr.GetInt32(11).ToString();
lblquestionno.Text ="Question " + dr.GetInt32(0).ToString();
}
if (dr.GetString(9) == sMultiple)
{
grpmultipleanswers.Visible = true;
grpsingleanswers.Visible = false;
txtquestion.Text = dr.GetString(2);
cmbqtype.SelectedItem = dr.GetString(9);
cmbcomplexity.SelectedItem = dr.GetString(10);
lblscore.Text = dr.GetInt32(11).ToString();
//lblquestion.Text = dr.GetInt32(0).ToString();
lblquestionno.Text = "Question " + dr.GetInt32(0).ToString();
//lblquestion.Text = "Question" + " " + dr.GetInt32(0).ToString();
txtchkchoiceA.Text = dr.GetString(3);
txtchkchoiceB.Text = dr.GetString(4);
txtchkchoiceC.Text = dr.GetString(5);
txtchkchoiceD.Text = dr.GetString(6);
txtchkchoiceE.Text = dr.GetString(7);
txtchkchoiceF.Text = dr.GetString(8);
}
}
//btnfirst.Hide();
btnview.Hide();
btnupdate.Show();
conn.Close();
}
catch (Exception ex)
{
MessageBox.Show("Error Occured" + ex);
}

Button Update

try
{
SqlConnection conn = new SqlConnection(@"Data Source = (LocalDB)\MSSQLlocaldb; Initial Catalog = AdminAuthentication; Integrated Security = True");
var query = "update Questions Set QText= @QText, ChoiceA=@ChoiceA, ChoiceB=@ChoiceB,ChoiceC=@ChoiceC,ChoiceD=@ChoiceD, ChoiceE=@ChoiceE,ChoiceF=@ChoiceF,QType=@QType,QComplexity=@QComplexity,QPoints=@QPoints,AuthorizationCode=@AuthorizationCode,Exhibit=@exhibit WHERE QID=@QID";
var cmd = new SqlCommand(query, conn);
conn.Open();
cmd.Parameters.AddWithValue("@QID", SqlDbType.Int).Value = lblquestion.Text;
cmd.Parameters.AddWithValue("@QText", SqlDbType.VarChar).Value = txtquestion.Text;
cmd.Parameters.AddWithValue("@ChoiceA", SqlDbType.VarChar).Value = txta.Text;
cmd.Parameters.AddWithValue("@ChoiceB", SqlDbType.VarChar).Value = txtb.Text;
cmd.Parameters.AddWithValue("@ChoiceC", SqlDbType.VarChar).Value = txtc.Text;
cmd.Parameters.AddWithValue("@ChoiceD", SqlDbType.VarChar).Value = txtd.Text;
cmd.Parameters.AddWithValue("@ChoiceE", SqlDbType.VarChar).Value = txtchkchoiceE.Text;
cmd.Parameters.AddWithValue("@ChoiceF", SqlDbType.VarChar).Value = txtchkchoiceF.Text;
cmd.Parameters.AddWithValue("@QPoints", SqlDbType.Int).Value = lblscore.Text;
cmd.Parameters.AddWithValue("@QType", SqlDbType.VarChar).Value = cmbqtype.SelectedItem;
cmd.Parameters.AddWithValue("@QComplexity", SqlDbType.VarChar).Value = cmbcomplexity.SelectedItem;
cmd.Parameters.AddWithValue("@AuthorizationCode", SqlDbType.Int).Value = txtauthorizationcode.Text;
cmd.Parameters.Add(new SqlParameter("@exhibit", images));
cmd.ExecuteNonQuery();
txtquestion.Clear();
txta.Clear();
txtb.Clear();
txtc.Clear();
txtd.Clear();
txtchkchoiceA.Clear();
txtchkchoiceB.Clear();
txtchkchoiceC.Clear();
txtchkchoiceD.Clear();
txtchkchoiceE.Clear();
txtchkchoiceF.Clear();
lblquestion.Text = "";
lblquestionno.Text = "";
lblscore.Text = "";
cmbqtype.SelectedItem = null;
cmbcomplexity.SelectedItem = null;
//MessageBox.Show("Data succefully updated");
//this.Hide();
//AdminPanel ap = new AdminPanel();
//ap.Show();
////what next?
conn.Close();
}
catch (Exception ex)
{
MessageBox.Show("Error Occured" + ex);
}