[TYPO3-mvc] Dispatcher Ajax RootlineUtility warning

[RAKIBI Anass]

Hello Guys , 

I have created an extension that includes an Ajax call ( using the Ajax dispatcher ) , on my local environment it works smoothly .
But when I installed the extension on a production environment and try to make the ajax call , I get this error : 

PHP Warning: Invalid argument supplied for foreach() in /typo3/sysext/core/Classes/Utility/RootlineUtility.php line 271.

I checked that line and I think instead of getting an array , another type of argument gets passed .. I don't know what I really have to change 
because , as said , it works fine on my local machine . 

PS : the same version (6.2.69 is installed on both machines .