error report - by: dep@eca.fr

I've got an error message for Tickets report:

2016-04-26 09:38:46.964 ***** ERROR ***** ERROR *****
2016-04-26 09:38:46.964 ***** ERROR ***** on file '/var/www/projeqtor/tool/projeqtor.php' at line (936)
2016-04-26 09:38:46.964 ***** ERROR ***** cause = Undefined variable: logLevel
2016-04-26 09:39:32.241 ===== TRACE ===== NEW CONNECTED USER 'fde'
2016-04-26 14:31:38.470 ***** ERROR ***** ERROR *****
2016-04-26 14:31:38.477 ***** ERROR ***** on file '/var/www/projeqtor/tool/projeqtor.php' at line (936)
2016-04-26 14:31:38.478 ***** ERROR ***** cause = Undefined variable: logLevel
2016-04-26 14:33:04.457 ***** ERROR ***** ERROR *****
2016-04-26 14:33:04.457 ***** ERROR ***** on file '/var/www/projeqtor/external/pChart/pChart.class' at line (3184)
2016-04-26 14:33:04.457 ***** ERROR ***** cause = imagepng(): Unable to open '../file/report//user5_ticketYearlyReport_20160426_143304_1.png' for writing: No such file or directory