um_submit_form_errors_hook_ not working

function verify_id_number($id_number, $gender = '', $foreigner = 0) {
    $validated = false;
    if (is_numeric($id_number) && strlen($id_number) === 13) {
        $errors = false;
        $num_array = str_split($id_number);
        $id_month = $num_array[2] . $num_array[3];
        $id_day = $num_array[4] . $num_array[5];

        if ($id_month < 1 || $id_month > 12) {
            $errors = true;
        }
        if ($id_day < 1 || $id_day > 31) {
            $errors = true;
        }
        $id_gender = $num_array[6] >= 5 ? 'male' : 'female';
        if ($gender && strtolower($gender) !== $id_gender) {
            $errors = true;
        }
        $id_foreigner = $num_array[10];
        if (( $foreigner || $id_foreigner ) && (int)$foreigner !== (int)$id_foreigner) {
            $errors = true;
        }

        $even_digits = array();
        $odd_digits = array();
        foreach ($num_array as $index => $digit) {
            if ($index === 0 || $index % 2 === 0) {
                $odd_digits[] = $digit;
            } else {
                $even_digits[] = $digit;
            }
        }
        $check_digit = array_pop($odd_digits);
        $added_odds = array_sum($odd_digits);
        $concatenated_evens = implode('', $even_digits);
        $evensx2 = $concatenated_evens * 2;
        $added_evens = array_sum(str_split($evensx2));
        $sum = $added_odds + $added_evens;
        $last_digit = substr($sum, -1);
        $verify_check_digit = (10 - (int)$last_digit) % 10;
        if ((int)$verify_check_digit !== (int)$check_digit) {
            $errors = true;
        }
        if (!$errors) {
            $validated = true;
        }
    }
    return $validated;
}

add_action('um_submit_form_errors_hook', 'my_custom_validate_id_number', 10, 1);

function my_custom_validate_id_number($post) {
    // Assuming 'drivers_id_number' is the key of your field in the form
    $id_number = isset($post['drivers_id_number']) ? $post['drivers_id_number'] : '';

    // Perform your validation (calling a hypothetical validate_id_number function)
    if (!empty($id_number) && !validate_id_number($id_number)) {
        UM()->form()->add_error('drivers_id_number', 'Invalid ID Number');
    }
}

Please help me to debug this code,

What I need to achieve is to validate the ID number entered in UM form field. If it passes the form should be normally submitted, else display the error

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