Codeigniter Tasks do not work with cronjob

Hi, I have a question.
Firstly, this package work fine if we run manually from terminal. but when i implement it in cron its like php spark bla:bla do nothing. I can not reproduce any errors in cron.
my command in cron: * * * * * cd /Applications/MAMP/htdocs/projects/cosmos && touch taskstarting.php && php spark tasks:run && touch taskstopping.php >> /dev/null 2>&1
I can see taskstarting.php inside my project. but, I can not see taskstopping.php inside my project that indicated php spark do nothing in cron.
Let me know how to achieve this, Thanks in advance.