Meraki MX100 shows 0 MBytes sent/received bytes in ManageEngine Firewall Analyzer

Meraki MX100 shows 0 MBytes sent/received bytes in ManageEngine Firewall Analyzer

I have enabled Syslog in MX100 with all available roles, and also enabled "logging" options an all firewall rules. I use "ManageEngine Firewall Analyzer" as Syslog server, currently it can reads events and hits, VPN access etc. but all reports are shown with zero MBytes traffic. What could be the issue?