private function removeCurrencySymbol(string $value, string $currency): string
    {
        $locale = \Locale::getDefault();

        if (!isset(self::$patterns[$locale][$currency])) {
            // Initialize the cache, ignore return.
            $this->addCurrencySymbol('123', $currency);
        }

        return preg_replace('#(\s?'.preg_quote(self::$patterns[$locale][$currency][1], '#').'\s?)#u', '', $value);
    }