[ureech]

Например так

...
      success: function (data) {
            let obj = JSON.parse(data);

            let row = document.createElement('div');
            row.className = 'row';

           let div = [];
            for (var key in obj) {
            div[key] ='....';
            }
 $(div).before(row);

 $('.ajax-items .row').html(div)

Uncaught TypeError: n[0] is undefined