Hello,
Regarding the question that the new VM cannot be activated, it is recommended that you call the activation number to solve the issue.
Regarding the second question,
Windows Server Standard Edition licenses include permissions for two VMs.
If you need to run more than two VMs, you'll need to purchase additional licenses. With each additional 1 or 2 VMs, you need to purchase a license again for all the physical cores of the server.
About official document, please refer to this link:
https://www.microsoft.com/en-us/windows-server/pricing?msockid=122c9882be3e6b443dbe8c38bf556abb
Best Regards,
Hania Lian
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