This issue is occuring only in IE 11

There are no server side errors on page, on event binding for this textbox this appears every time and adding the attendee for the 2nd time. Here is the source code:

jQuery("#field27").jqGrid({
       url:'tempattendees.php?Field_ID=1426',
    editurl:'tempattendeesedit.php',
    datatype: "json",
       colNames:['ID', 'First Name', 'Last Name', 'Job Title', 'Company', 'Email', 'Phone', 'f'],
       colModel:[
        {name:'AddressBook_ID',index:'AddressBook_ID',editable:true, hidden: true},
        {name:'FirstName',index:'FirstName',editable:true,editrules:{required:true}},
        {name:'LastName',index:'LastName',editable:true,editrules:{required:true}},
        {name:'Job_Title',index:'Job_Title',editable:true},
        {name:'Company',index:'Company',editable:true},
        {name:'Email',index:'Email',editable:true,editrules:{required:true}},
        {name:'Phone',index:'Phone',editable:true},
        {name:'Field_ID',index:'Field_ID',hidden: true, editable: true, editrules: { edithidden: false }, editoptions: { defaultValue:'1426'}, hidedlg: true}
       ],    
    jsonReader : { id: "AddressBook_ID"},    
    width:600,
    height:100,
       rowNum:50,
       rowList:[15,30,50],
       pager: '#field27pager',
       sortname: 'FirstName',
    viewrecords: true,
    sortorder: "desc",
    caption:"Customer/Partner Attendees",     
    gridComplete: function() { $("#_empty","#field27").addClass("nodrag nodrop"); jQuery("#field27").tableDnDUpdate(); }     
});

jQuery("#field27").jqGrid('navGrid','#field27pager',{edit:true,add:true,del:true});

// Resizing
jQuery("#field27").jqGrid('gridResize',{minWidth:350,maxWidth:800,minHeight:80, maxHeight:350});
    });