Hi,
From the Active Directory side, it is suggested to check if all DCs are working well, and at the same time, check the replication status among DCs.
Following commands for your reference:
Dcdiag /v >c:\dcdiag1.log
Repadmin /showrepl >C:\repl.txt
Repadmin /showreps *
If all works well, you may try to get more details from the even view.
Or you can consider capturing the network packages when you re-produce the issue.
Best Regards,