[solved] Is it possible to activate license without connecting to internet?

[Cloudsrest]

We install the MinimServer 2 to our Qnap TS-328. It works well with starter, but we want to activate the trial license to see how it works, then we can activate the full license.
The problem is that we like to keep our music system simple , only stay in our local home network, and never want our NAS to connect to internet.
I wonder if we can activate the license without connecting to internet...

Thanks very much!