Timer Problem in multi user online exam system

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C#

ASP.NET

timer

i have to develop multi user online exam system all work is completed but one problem is that
when another user login in exam system then his timer value change the previous user Timer value.
i have use 2 static int value for minute and second.
Please help my code is

static int tmpStartmin = 0;
static int tmpStartSecond = 59;

 protected void SetExamTimer()
    {

        Timer1.Enabled = false;
        if (Session["QStartTime"] == null)
            Session.Add("QStartTime", DateTime.Now);
        else
            Session["QStartTime"] = DateTime.Now;
        SqlConnection sqcontime = new SqlConnection(System.Configuration.ConfigurationManager.ConnectionStrings["ConnectionStr"].ConnectionString);
        string sqtime = "";
        DataTable dtt = new DataTable();
        sqtime = "Select Top 1 * from TimeLog Where QuestionPaper_ID=" + int.Parse(Session["QuesPaper_ID"].ToString()) + " and Registration_ID=" + int.Parse(Session["RegistrationID"].ToString()) + " and isdeleted=0 Order by Timelog_Id desc ";
        SqlDataAdapter adptime = new SqlDataAdapter(sqtime, sqcontime);
        adptime.Fill(dtt);
        if (dtt.Rows.Count > 0)
        {
            divTime.Visible = true;
            Timer1.Enabled = true;
            if (Session["QStartTime"] == null)
                Session.Add("QStartTime", DateTime.Now);
            else
                Session["QStartTime"] = DateTime.Now;
            lblTime.Text = dtt.Rows[0]["Time"].ToString();          
            tmpStartmin = Convert.ToInt32(dtt.Rows[0]["Min"].ToString());
            tmpStartSecond = Convert.ToInt32(dtt.Rows[0]["Sec"].ToString());
            lblMinute.Text = tmpStartmin.ToString();
            lblSeconds.Text = tmpStartSecond.ToString();

        }
        else
        {


            string sqq = "";
            DataTable dt = new DataTable();
            sqq = "Select * from StDetail Where QuestionPaper_ID=" + int.Parse(Session["QuesPaper_ID"].ToString()) + " and isdeleted=0";
            SqlDataAdapter dq = new SqlDataAdapter(sqq, System.Configuration.ConfigurationManager.ConnectionStrings["ConnectionStr"].ConnectionString);
            dq.Fill(dt);
            if (dt.Rows.Count > 0)
            {
                divTime.Visible = true;
                Timer1.Enabled = true;
                if (Session["QStartTime"] == null)
                    Session.Add("QStartTime", DateTime.Now);
                else
                    Session["QStartTime"] = DateTime.Now;
                lblTime.Text = dt.Rows[0]["FixedExamTime"].ToString();
                tmpStartmin = Convert.ToInt32(dt.Rows[0]["FixedExamTime"].ToString()) - 1;
                lblMinute.Text = tmpStartmin.ToString();
                lblSeconds.Text = tmpStartSecond.ToString();
            }
            else
            {
                divTime.Visible = false;
                Timer1.Enabled = false;
                if (Session["QStartTime"] == null)
                    Session.Add("QStartTime", DateTime.Now);
                else
                    Session["QStartTime"] = DateTime.Now;
            }


        }
    }