This article describes how to upgrade the VM license in
order to use more vCPU and RAM.Follow the link here below for VM license specifications:https://www.fortinet.com/content/dam/fortinet/assets/data-sheets/fortigate-vm.pdf
# execute restore vmlicense tftp FGVM***********.lic 192.168.193.1This operation will overwrite the current VM license!Do you want to continue? (y/n)yPlease wait...Connect to tftp server 192.168.193.1 ...
Get VM license from tftp server OK.VM license install succeeded. Rebooting firewall.