Retain table and checked checkboxes after postback

In my webpage, I have Calendar, Table and button.

After selecting date, it will fire the databind() method of table. There are checkboxes with autopostback =true. Once checked, the Table disappears. I have no idea on how to retain the table with the checked checkboxes after post back.

 protected void Page_Load(object sender, EventArgs e)
    {
        if (Request.QueryString.Get("Id") != null)
        {

            if (!IsPostBack)
            {
                Calendar1.Visible = false;

            }
        }
    }

 protected void Calendar1_SelectionChanged(object sender, EventArgs e)
        {
            Label1.Text = Calendar1.SelectedDate.ToShortDateString();
             //Set datasource = (cal.selectedDate), the invoking override 
                 // DataBind() method to create table

                }
            Calendar1.Visible = false;

        }

I've tried to databind the table again else (IsPostBack) but i wasn't able to achieve my goals, instead, it created another table on top of the existing table