A separate license is required for each installation, including installations on subdomains. Every WordPress installation and every instance (individual site) within a WordPress Multisite network requires its own license.
Example: If you use a Network Multisite with 10 instances (websites), you need 10 licences.
You can upgrade your license cost-effectively in the customer portal at https://service.borlabs.io/login.
For more information about upgrading your license, please refer to: Upgrade licence