ocs inventory package activation page is empty

Hello,

I have updated my server to the last version and I got just 1 issue for the moment, the package activation is empty even if I upload a package (.zip) to my server : 

But into my download folder I see it : 

root@fr1-ls-01:~# ls -l /var/lib/ocsinventory-reports/download/
total 4
drwxr-xr-x 2 www-data www-data 4096 avril 25 18:13 1493136731
root@fr1-ls-01:~#

Do you have some idea why ? 

Thank you for your help.