Cubase 12.0.60 will not start without internet connection

My DAW is not connected to the internet.

Now, when I start, I get a dialog window which says:

Steinberg Activation Manager
We are sorry, a network problem occurred.
We could not contact our license servers. Your computer may not be connected to the internet or our servers may be unavailable.
Please ensure you are connected to the internet. If the problem persists, please try again later.
[ Quit ] [ Retry ]

There is a window over that one, positioned directly in the middle:
No valid License found. The program will quit now.
[ OK ]

At the bottom left it says:

Checking Licenses…

It worked fine last time I used it a month or two ago.
I don’t remember if I was connected to the internet at that time.
Is it a requirement that I be connected to the internet?
I don’t remember reading that anywhere when I checked the details before I purchased it.

Edit: I just tried on my second PC, and it starts up without internet no problem.
Last time I started it was more recently, perhaps 1 month.
What could be causing the issue?

If anything OS or hardware wise has changed on your system then Cubase will be asked to reactivate via the Activation manager which does require the internet BUT once that’s done and nothing changes on your system then there’s no internet needed after

May be this helps: