Fortianalyzer duplicate license

Hope this helps:

https://community.fortinet.com/t5/FortiWeb/Troubleshooting-Tip-Duplicate-license-has-been-detected/ta-p/203372

Any help?

Did you install the VM on a proxmox environment ?

Maybe this comment will help, 

Run  "diagnose debug vminfo" - if you don't see value for "VU UUID" then you're in trouble - this (and Serial Number) is sent to Fortinet to verify license

from https://community.fortinet.com/t5/Support-Forum/FAZ-VM-Duplicate-License-Trial-7-4-1/m-p/298157/highlight/true

what version of FAZ VM did you install ?