Hello Soar,
Thank you for posting in our Q&A forum.
How many DCs are there in your domain?
If you check newly created OU or group one DC, whether you check the OU or/ and group in Group Policy Management in the same DC?
If so, I suggest you can close Group Policy Management tool and reopen Group Policy Management tool to check the new OU you created.
Or maybe you have multiple, you can if check AD replication is complete on these DCs.
Hope the information above is helpful. If you have any question or concern, please feel free to let us know.
Best Regards,
Daisy Zhou
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