[SOLVED] Unable to get all fields for PROJECT in template report

Hello,

i'm trying to get all fields values for a project by building a custom report with all of then (from fields list in template report module).
You can see template in attachment.

When generating template, i get this error :2023-09-06 13:18:02.256 ***** ERROR ***** [V10.4.4] ERROR *****
2023-09-06 13:18:02.256 ***** ERROR ***** [V10.4.4] on file 'C:\xampp-\htdocs\external\tbs\tbs_class.php' at line (3850)
2023-09-06 13:18:02.256 ***** ERROR ***** [V10.4.4] cause = Array to string conversion

I found the error : i keep the header for group in my template (ie : [incomming]) that cause the error.
I remove it and it works fine !