PHP Catchable fatal error in Laravel 5.4 -

i have site developed laravel 5, of sudden have been having error , did not make changes.

php catchable fatal error: argument 1 passed recursiveiteratoriterator::__construct() must instance of traversable, instance of symfony\component\finder\iterator\excludedirectoryfilteriterator given, called in /home/reor/vendor/symfony/finder/finder.php on line 571 , defined in /home/reor/vendor/symfony/finder/finder.php on line 675

the site hosted on shared hosting account. can have caused error. thanks