Office KMS Stopped Activating

[Jobos]

Our KMS has stopped activating clients and I'm unsure why.

 

We have a mix of Office 2021 LTSC and Office 2024 LTSC but as the older versions pass my desk they get upgraded to 2024. This morning I upgraded another laptop to 2024 LTSC and it didn't activate so on checking the KMS server both Office 2021 and Office 2024 have the status of unlicenced. Windows server and Office 2019 is still licenced though.

 

What would cause this and what is the best way forward to resolve it?

 

Thanks.

[Jobos]

Seems the KMS server just needed activating again using

cscript C:\Windows\System32\slmgr.vbs /act F3D89BBF-C0EC-47CE-A8FA-E5A5F97E447F