FortiSandbox provides a solution to protect against advanced threats and ransomware for companies who don’t want to implement and maintain a sandbox environment on their own.
Article Id 196324

This article describes how to activate free FortiSandbox Cloud when purchased antivirus license under UTP bundle.

Important Notes:
Purchased first theAV license under UTP bundle. Otherwise, this solution will not work.
- By default, having the antivirus license alone will prevent from enable the FortiSandbox cloud from the GUI because it requires to have FortiSandbox Cloud entitlement.
- Activating Fortigate cloud is required before enable FortiSandbox Cloud under antivirus license. 
Make sure that it is showing as 'Activated' on the dashboard. 
It is also possible to use the following command to Login to the FortiGate Cloud account if it is already registered:
# exec fortiguard-log login <email> <password>
- For more web login or account registration,  refer to the following link:
- Activate FortiSandbox Cloud using the following command and select the region:
# execute forticloud-sandbox region
- Cross-check on the FortiSandbox Fabric Connector and it will be enabled.