How can I achieve the desired result below using C# ASP.NET?

See more:

MySQL

ASP.NET4

i want to display 3 records from database if any data is null or blank i should get not data available error on that column.but all 3 column should be displayed in page.kindly help

<a href="https://ibb.co/48kF0Sz"></a>

What I have tried:

 try
  {
      MySqlConnection con = new MySqlConnection(constr);
      MySqlCommand cmd = new MySqlCommand();
      cmd.CommandText = "select md.M_Name from F_SubMembers_Details sm Inner
      Join FMember_Details md on md.M_Id = sm.Sub_Id where sm.M_Id = @S_Id
      limit 3 ";
      cmd.Parameters.AddWithValue("@S_Id", Session["name"].ToString());
      cmd.Connection = con;
      con.Open();
      Repeater_ClientSection.DataSource = cmd.ExecuteReader();
      Repeater_ClientSection.DataBind();
      foreach (RepeaterItem item in Repeater_ClientSection.Items)
      {

          Label lbl1 = (Label)item.FindControl("lblcname");
          if (lbl1.Text == "Null" || lbl1.Text == "")
          {
              lbl1.Text = "Item Not available";
          }

      }
      con.Close();
    }
  catch (Exception ex)
  {

  }
<asp:Repeater ID="Repeater_ClientSection" runat="server" Visible="true">
              <ItemTemplate>
 <div class="col-md-4 col-sm-6">
  <div class="serviceBox">
      class="service-icon fa fa-globe">
      <asp:Label ID="lblcname" runat="server" CssClass="title" Text='<%#
      Eval("M_Name") %> ' />

      <a href="#" class="read-more">
          <span>Read More</span>
          ^__i class="fa fa-angle-right">
      </a>
  </div>
  </div>
  </ItemTemplate>
  </asp:Repeater>