Hello,
Thank you for posting in Q&A forum.
To further troubleshoot this issue, please kindly try below steps:
1.Check if the Microsoft Key Distribution Service is set to Automatic.
2.Check if there are any differences in the configuration or policies between the parent domain and the subdomains.
3.Check event log and see if there's any related errors like eventID 7038.
4.Ensure that the network and DNS configurations are correctly set up.
I hope the information above is helpful.
If you have any questions or concerns, please feel free to let us know.
Best regards,
Jill Zhou
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