cemba

do you see the console log(datalayer) in your browser console?
Yes i see datalayer on console log but empty array

any JS error in the browser console?
no jserror

do you use dataLayer.push on other places in your site, and it works there?
yep i used it for multiple trigger form and it worked.

used this function type for other forms;

function dtGelisim(){
  var statuse = document.querySelectorAll("#statusId li.active a span")[0].innerText;
  
    var today = new Date();
    var selectedday = new Date(document.getElementsByName("BDAY")[0].value);
    var oneDay = 24 * 60 * 60 * 1000;
    var diffDays = Math.round(Math.abs((selectedday - today) / oneDay));
    
    dataLayer.push({
    'event': 'FormSubmit',
    'MainCategory': 'xx',
    'SubCategory': 'xx',
    'Status': statuse,
    'RemainingDay': diffDays,
    'Kvkk': 'Yes'
    });
    console.log(dataLayer);
 }