Why i can't add Cron entry to my ubuntu 18.04 server?

Created laravel artisan Command to execute inside Laravel 5.5 Scheduler (every month).

When i try add Cron entry to my ubuntu 18.04 server with command line :

• • • • • php /var/www/public_html/laravel-project-name/artisan schedule:run

i get this error : zsh: command not found: app

output error: zsh: command not found: app

Note: cmd : $ php artisan schedule:run

Work just fine

Starting The Scheduler

via Chebli Mohamed