Hi,
Thank you for posting your query.
Kindly follow the steps provided below to resolve your issue.
To use KMS, you need to have a KMS host available on your local network. Computers that activate with a KMS host need to have a specific product key. This key is sometimes referred to as the KMS client key, but it is formally known as a Microsoft Generic Volume License Key (GVLK). Computers that are running volume licensing editions of Windows Server and Windows client are, by default, KMS clients with no extra configuration needed as the relevant GVLK is already there.
Go to this link for your reference and other troubleshooting procedures https://learn.microsoft.com/en-us/windows-server/get-started/kms-client-activation-keys
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