我的项目在服务器上给出此错误，但在本地系统中工作良好.FormatException:字符串没有被识别为有效的日期时间

我的软件在服务器上给出这个错误

系统。FormatException:字符串未被识别为有效的日期时间。

它在本地工作很好，我使用jquery的日期时间。我的日期格式是dd-mm-yyyy，它昨晚工作正常，但早上给我这个错误。

protected void btnapprove_Click(object sender, EventArgs e)
{
    if (btnapprove.Text == "Approve")
        if (txtremark.Text != "")
        {
            fillSaveapprove();
            SaveProposalregis["IsActive"] = "Approve";
            string str = lo.SaveProposalregis(SaveProposalregis);

            if (str == "Save")
            {
                cleartext();
                ScriptManager.RegisterStartupScript(Page, Page.GetType(), "alert", "alert('Approve Successfull')", true);
                GridViewregis.DataBind();
                panelgridview.Visible = true;
                GridViewregis.Visible = true;
            }
            else
            {
                ScriptManager.RegisterStartupScript(Page, Page.GetType(), "alert", "alert('Status Not Update SuccessFully')", true);
                panelgridview.Visible = false;
                panelshow.Visible = false;
            }
        }
        else
        {
            ScriptManager.RegisterStartupScript(Page, Page.GetType(), "alert", "alert('Please Fill Remark')", true);
            panelgridview.Visible = true;
            panelshow.Visible = true;
        }
}
public void fillSaveapprove()
{
    SaveProposalregis["id"] = Convert.ToInt64(hid.Value);
    SaveProposalregis["plvcid"] = Convert.ToInt64(plvcid.Value);
    SaveProposalregis["bankname"] = lblbankname.Text;
    SaveProposalregis["Address"] = lbladd.Text;
    SaveProposalregis["First_Name"] = lblfirstname.Text;
    SaveProposalregis["Last_Name"] = lblln.Text;
    SaveProposalregis["Father_Name"] = lblfn.Text;
    SaveProposalregis["DOB"] = lbldob.Text;
    SaveProposalregis["Contact_No"] = lblconno.Text;
    SaveProposalregis["Email_Id"] = lblemail.Text;
    SaveProposalregis["Pan_Detail"] = lblpanno.Text;
    SaveProposalregis["Nominee_Name"] = lblnomineename.Text;
    SaveProposalregis["Gender"] = lblngender.Text;
    SaveProposalregis["nominee_dob"] = lblndob.Text;
    SaveProposalregis["nominiRelationwithroposer"] = lblnrwp.Text;
    SaveProposalregis["l_a_Name"] = lbllaname.Text;
    SaveProposalregis["l_a_gender"] = lbllagender.Text;
    SaveProposalregis["l_a_dob"] = lblladob.Text;
    SaveProposalregis["l_a_Relationwithroposer"] = lbllarew.Text;
    SaveProposalregis["Application_No"] = lblappno.Text;
    SaveProposalregis["Plan"] = lblplan.Text;
    SaveProposalregis["Company_name"] = lblcompname.Text;
    SaveProposalregis["Primium_paying_Term"] = lblppt.Text;
    SaveProposalregis["Policy_Term"] = lblpt.Text;
    SaveProposalregis["Mode_of_Payment"] = lblmop.Text;
    SaveProposalregis["Cheque_No"] = lblcn.Text;
    SaveProposalregis["Cheque_Amount"] = lblcamount.Text;
    SaveProposalregis["Cheque_Date"] = lblchqdate.Text;
    SaveProposalregis["Demand_Draft_No"] = lblddno.Text;
    SaveProposalregis["DD_Payee_Name"] = lblddpayeename.Text;
    SaveProposalregis["DD_amount"] = lblddamount.Text;
    SaveProposalregis["dd_Date"] = lbldddate.Text;
    SaveProposalregis["Primium_mode"] = lblprimiummode.Text;
    SaveProposalregis["Employeee_code"] = lblempcode.Text;
    SaveProposalregis["Manager"] = lblmanager.Text;
    SaveProposalregis["Tl_name"] = lbltlname.Text;
    SaveProposalregis["tc_name"] = lbltcname.Text;
    SaveProposalregis["GrossPrimium"] = lblgrossprimium.Text;
    SaveProposalregis["NetPrimium"] = lblnetprimium.Text;
    SaveProposalregis["ModelPrimium"] = lblmodelprimium.Text;
    SaveProposalregis["RegistrationDate"] = lbldate.Text;
    SaveProposalregis["country"] = lblcountry.Text;
    SaveProposalregis["state"] = lblstate.Text;
    SaveProposalregis["city"] = lblcity.Text;
    SaveProposalregis["pinno"] = lblpinno.Text;
    SaveProposalregis["alternateno"] = lblalternateconno.Text;
    SaveProposalregis["Remark"] = txtremark.Text;
    SaveProposalregis["PlvcStatus"] = "Approve";

}`