Trial License for FortiGate VM (Learning & Certification)

I am currently preparing for the Fortinet Certified Professional (FCP) certification in Network Security. As part of my hands-on learning and practical lab setup, I have successfully installed the FortiGate VM on my local environment.

However i am finding it hard to access the GUI of the FortiGate VM due to absence of a trial license.
i have tried this commands 

execute vm-license-options account-id xxxx@fortinet.com

execute vm-license-options account-password xxxxxxx

execute vm-license

It showed the error 
"Requesting Forticare Trial license, proxy:(null)
failed to download VM license"

I would like to kindly request help in acquiring trial license for the FortiGate VM. This is meant exclusively for my study and practice and learning experience. Community help will be very much appreciated :'(