The form on the site is not being sent, what could be the error?

Question

AJAX

The form is not sent, it gives an error in this section of the code. Help)

const form = document.getElementById('form-contacts');
form.addEventListener('submit', formSend);

async function formSend(e) {
        e.preventDefault();

        let error = formValidate(form);

        let formData = new FormData(form);

        if (error === 0) {
            let response = await fetch('sendmail.php', {
                method: 'POST',
                body: formData
            });
            if (response.ok) {
                let result = await response.json();
                succesModal.classList.add('active');
                alert(result.message);
                formPreview.innerHTML = '';
                form.reset();
            } else {
                alert("Что-то пошло не так. Пожалуйста, повторите попытку.");
            }
        } else {
            editModal.classList.add('active');
        }
}