po provedeni kódu jQuery se vykoná pouze jednou

   $("body").on("click", "a.new-line", function () {
         ....
      $.ajax({
      type: 'post',
     url: '?do=edititem',
     data: {
        param: {
               ....
        },
     },
     success: function (response) {
          ....
     },
     error: function (response) {
          .....
        }
      })
   });

   $("body").on("click", "a.new-line", function () {
      $("div#ajax-spinner").show();
      var myid = $(this).attr('data-id');

      $.ajax({
     type: 'post',
     url: '?do=edititem',
     data: {
        param: {
           EmployeeNumber: $('#frm-absence-employee').val(),
           FirstDayDate: $('input.FirstDayDate').val(),
           LastDayDate: $('input.LastDayDate').val(),
           AbsenceType: $('#select-absence option:selected').text(),
           AbsenceRemark: $('input.AbsenceRemark').val()
        },
     },
     success: function (response) {
             $('form#frm-absence').on('submit');
     },
     error: function (response) {
        console.log(response);
     }
      })

      $("div#ajax-spinner").hide();
   });

          ....
     $("body").on('click', "a.editmytab", function () {
        alert('ahoj');
     });
     $("div#ajax-spinner").hide();