更新用户信息，但没有更新且没有错误

Question

我正在尝试更新多个用户信息，但不会更新。我已经尝试了很多方法，所有方法都会执行，但是它们不会更新数据，但没有丢失错误。我想念什么吗？

这是代码：

protected void Update_Click(object sender, EventArgs e)
{
    using (SqlConnection sqlCon = new SqlConnection(connectionstring))
    {
        sqlCon.Open();

        using (var sqlStt = sqlCon.CreateCommand())
        {
            sqlStt.CommandType = CommandType.Text;
            sqlStt.CommandText = "UPDATE USERS SET LAST_NAME = @LAST_NAME, FIRST_NAME = @FIRST_NAME, BIRTHDATE = @BIRTHDATE, PHONE_NUM = @PHONE_NUM, EMAIL = @EMAIL WHERE USERNAME ='" + Session["USERNAME"] + "' ";

            sqlStt.Parameters.AddWithValue("@LAST_NAME", Lname.Text);
            sqlStt.Parameters.AddWithValue("@FIRST_NAME", Fname.Text);
            sqlStt.Parameters.AddWithValue("@BIRTHDATE", Birthdate.Text);
            sqlStt.Parameters.AddWithValue("@PHONE_NUM", Phone_num.Text);
            sqlStt.Parameters.AddWithValue("@EMAIL", Email.Text);

            sqlStt.ExecuteNonQuery();
        }

        sqlCon.Close();

        Display_Info();
        Disable_Field();
        Notificationtext.Text = "Your account has been updated!";
    }
}

void Disable_Field()
{
    Lname.Enabled = false;
    Fname.Enabled = false;
    Birthdate.Enabled = false;
    Phone_num.Enabled = false;
    Email.Enabled = false;
}

void Display_Info()
{
    using (SqlConnection sqlCon = new SqlConnection(connectionstring))
    {
        sqlCon.Open();

        SqlCommand sqlCmd = new SqlCommand("SELECT LAST_NAME, FIRST_NAME, BIRTHDATE, PHONE_NUM, EMAIL FROM USERS WHERE USERNAME ='" + Session["USERNAME"] + "' ", sqlCon);

        SqlDataReader reader;
        reader = sqlCmd.ExecuteReader();

        if (reader.Read())
        {
            Lname.Text = reader["LAST_NAME"].ToString();
            Fname.Text = reader["FIRST_NAME"].ToString();
            Birthdate.Text = reader["BIRTHDATE"].ToString();
            Phone_num.Text = reader["PHONE_NUM"].ToString();
            Email.Text = reader["EMAIL"].ToString();
        }

        sqlCon.Close();
    }
}

我还想将更新显示到文本框，然后将其禁用。单击更新后，更新之前的数据将显示。