Display DataList selected item based record in FormView on Button click using C# in ASP.Net

 datalist by button click and display record on formview in model using Username

here is what i tried

<asp:DataList ID="GetMergedAll." runat="server">

<asp:Label ID="Name" runat="server" Text="Label"></asp:Label>
<asp:Label ID="Post" runat="server" Text="Label"></asp:Label>
<asp:LinkButton ID="LinkButton6" runat="server">LinkButton</asp:LinkButton>


</asp:DataList>

 protected void Page_Load(object sender, EventArgs e)
    {

        //  int.Parse(Request.QueryString["Id"].ToString());


        if (Session["UserName"] != null && Session["UserName"].ToString() != string.Empty)
        {


            Session["Id"] = Session["Id"].ToString();
            Session["Name"] = Session["Name"].ToString();
            string username = Session["UserName"].ToString();
            string id = Session["UserName"].ToString();







            GetPost(username);
        }
    }


    public void GetPost(string username)
    {
        // int followerid;
        //  int followingid;
        string str = ConfigurationManager.ConnectionStrings["conn"].ConnectionString;
        string getADPOST = "GetMessage";
        using (SqlConnection con = new SqlConnection(str))
        {
            con.Open();
            using (SqlCommand cmd = new SqlCommand(getADPOST, con))
            {
                cmd.CommandType = CommandType.StoredProcedure;
                cmd.Parameters.AddWithValue("@UserName", username);
              
                //   cmd.Parameters.AddWithValue("@FriendUserName", username);
                //     cmd.Parameters.AddWithValue("@FollowingId", follower);
                //   
                SqlDataAdapter da = new SqlDataAdapter(cmd);
               // DataTable ds = new DataTable();
                DateTime.Now.AddDays(-5);
                DataTable ds = new DataTable();
                ds.Columns.AddRange(new DataColumn[3] { new DataColumn("Id", typeof(int)),
                    new DataColumn("Name", typeof(string)),
                    new DataColumn("Description",typeof(string)) });
                
                da.Fill(ds);
                //


                GetMergedAll.DataSource = ds;
                GetMergedAll.DataBind();
            }

on formview in model

 public void GetProfile(string username2)
    {
        string str = ConfigurationManager.ConnectionStrings["conn"].ConnectionString;
        string getADPOST = "GetPost";


        using (SqlConnection con = new SqlConnection(str))
        {
            con.Open();
            using (SqlCommand cmd = new SqlCommand(getADPOST, con))
            {
                cmd.CommandType = CommandType.StoredProcedure;
                cmd.Parameters.AddWithValue("@UserName", username2);
                //  cmd.Parameters.AddWithValue("@FriendUserName", Request.QueryString["Id"].ToString());
                cmd.Parameters.AddWithValue("@FriendUserName", username2);
               
                SqlDataAdapter da = new SqlDataAdapter(cmd);
                DataTable ds = new DataTable();
               
                da.Fill(ds);


              Post.DataSource = ds;
               Post.DataBind();
            }
            // conn.close();
        }
    }

html

 model here

   <asp:FormView ID="Post" runat="server">
<asp:Label ID="Name" runat="server" Text="Label"></asp:Label>
<asp:Label ID="Post" runat="server" Text="Label"></asp:Label>
</asp:FormView>