Laravel 5.4 Cron Job for Mail Queue not working on AWS EC2 instance

I have created a cron job on my EC2 instance for sending email from queue. It shows running the corn command every minute but I see tasks remain in my jobs table. I've already searched and tried existing solutions but failed to figure out the problem. Although queue working on my local server when I run php artisan schedule:run

My code in kernel:

$schedule->command('queue:work')
            ->everyMinute()
            ->withoutOverlapping();

Command I added in the file using crontab -e

* * * * * /usr/bin/php /var/www/html/prod_back/artisan schedule:run >> /dev/null 2>&1

This is the output I see in terminal when I run sudo service cron status

May 07 13:50:01 ip-172-31-39-27 CRON[20260]: pam_unix(cron:session): session opened for user ubuntu by (uid=0)
May 07 13:50:01 ip-172-31-39-27 CRON[20261]: (ubuntu) CMD (/usr/bin/php /var/www/html/prod_back/artisan schedule:run >> /dev/null 2>&1)
May 07 13:50:01 ip-172-31-39-27 CRON[20260]: pam_unix(cron:session): session closed for user ubuntu

via Chebli Mohamed