public function getFullMessage(): string {
        $paras = [];

        if (!empty($this->getMainMessage())) {
            $paras[] = $this->getMainMessage();
        } elseif ($this->getErrorCount() === 0) {
            return '';
        }

        if (isset($this->errors[''])) {
            $paras[] = $this->formatErrorList('', $this->errors['']);
        }

        foreach ($this->errors as $field => $errors) {
            if ($field === '') {
                continue;
            }
            $paras[] = $this->formatErrorList($field, $errors);
        }

        $result = implode("\n\n", $paras);
        return $result;
    }