I'am using another domain. I am using Php 7.4. The mail sending function does not work somehow.Can someone help?

<?php
if(substr(basename($_SERVER['PHP_SELF']), 0, 11) == "imEmailForm") {
include '../res/x5engine.php';
$form = new ImForm();
$form->setField('Eposta Adresiniz', @$_POST['imObjectForm_23_1'], '', false);

$errorMessage = '';
if(@$_POST['action'] != 'check_answer') {
if(!isset($_POST['imJsCheck']) || $_POST['imJsCheck'] != '50B54606BF3094C6E1B2B27D5AEC848B' || (isset($_POST['imSpProt']) && $_POST['imSpProt'] != ""))
die(imPrintJsError());
$form->mailToOwner('***', '', '***', 'Bize Ulasin', "", false);
@header('Location: ../index anasayfa.html');
exit();
} else {
echo $form->checkAnswer(@$_POST['id'], @$_POST['answer']) ? 1 : 0;
}
}

// End of file

Thanks.