lakshya this error occurred on your forum on 19th February (2 days ago), but it might be related since it seems to happen upon post deleting?
flarum.ERROR: Symfony\Component\Debug\Exception\FatalThrowableError: Argument 1 passed to FoF\Gamification\Listeners\RemoveVoteHandler::handle() must be an instance of Flarum\Post\Event\Deleting, instance of Flarum\Post\Event\Deleted given, called in /app/vendor/illuminate/events/Dispatcher.php on line 389 in /app/vendor/fof/gamification/src/Listeners/RemoveVoteHandler.php:20
That's the only error I see that happened on your forum recently. If it happens again, please check the console for errors too, as it could be a client-side issue
I remember this error happening a long time ago on my forum too, still not sure what was causing it. It seems that there are many reasons why it could fail