Django app problem

[Inside Believer]

DataTables warning: table id=filters-result-table - Ajax error. For more information about this error, please see http://datatables.net/tn/7

$('#input-search').keypress(function (e) {

        var key = e.which;

        if (key == 13)  // the enter key code

        {

            e.preventDefault();

            $(".btn-apply-filter").click()

        }

    });

    $('.btn-apply-filter').click(function (event) {

        let $from = $('#filter-form');

        let form_data = $("#filter-form").serializeArray();        

        var select_key 

        for (i=0; i<form_data.length;i++){                        

            if (form_data[i].name === 'select-key'){

                select_key = form_data[i].value

                

            }

            if (form_data[i].name === 'select-val'){

                if (select_key!=='-1' & form_data[i].value === ''){                    

                    toastr.error('Invalid/Empty filter value','Optional filter fields')

                    return

                }

            }

        }