Error log messages not showing anywhere


I have a really frustrating problem that I can't seem to solve. I have a CentOS VPS with OpenLiteSpeed web server installed and PHP.
I want to debug something in php so I use the error_log() function. But I can't find the message anywhere.

I have the following config for OLS web server:
- Server Configuration / Log -> File Name = "$SERVER_ROOT/logs/error.log", Log Leve = Warning
- Virtual Host / Log -> Use Server's Log = No, File Name = /var/log/litespeed/, Log Level = WARNING
(I attach screenshots)

I checked the following files and folders:
- /var/log/litespeed/ -> nothing
- /usr/local/lsws/logs -> nothing in any of the log files from there

Please help me because I don't know what to do further.

Thank you.