Here are a few commands that will help you confirm your KMS configuration.
To lookup current KMS servers run this in elevated cmd prompt:
nslookup -type=srv _vlmcs._tcp
To check your DNS for KMS servers:
Open DNS console and expand _tcp node under the domain.com.
Verify that there a record _VLMCS.
To Manually set a KMS server (for windows activation) run this command from an elevated cmd prompt:
slmgr.vbs /skms