No item in the deployment statistics lists

Hi,

All the lists are empty when I click on the number : "No data available in table". So i'm unable to known on which clients the package deployment are successfull or not.

I can see this line in Apache error log each time I try :

[Fri Jan 04 11:10:01.171630 2019] [:error] [pid XXXXX] [client my_IP_address:56766] PHP Warning:  mysqli_fetch_object() expects parameter 1 to be mysqli_result, boolean given in /usr/share/ocsinventory-reports/ocsreports/require/function_search.php on line 617, referer: https://server_IP_adress/ocsreports/index.php?function=visu_search&prov=stat&id_pack=1543418989&stat=***All%20the%20errors***

I run OCS Server 2.5 on Debian 9.0.

Let me know if I did'nt give required information.

Thanks a lot in advance.