public function get($key, $default = null)
    {
        $location = trim($this->config->get('mpesa.cache_location'), '/') . '/.mpc';

        if (! is_file($location)) {
            return $default;
        }

        $cache = unserialize(file_get_contents($location));
        $cache = $this->cleanCache($cache, $location);

        if (! isset($cache[$key])) {
            return $default;
        }

        return $cache[$key]['v'];
    }