ERROR 500 Cyberpanel

Hello Friends

Cyberpanel pages give me ERROR 500. all hosted websites and page work fine. I turned on debug mode with /usr/local/CyberCP/CyberCP/ and nothing happend. just error 500.

Also I checked cyberpanel database password in /usr/local/CyberCP/CyberCP/ and in /etc/cyberpanel/mysqlPassword and both are same.

What can I do with this issue?

Cyberpanel 2.0
UBUNTU 18.04

Thanks in advanced and I appreciate your help