I tried the same command and it worked for me as expected in my lab. I used below command,
You can also try to create the user first using powershell and then move the user to specific OU using below command,
Move-ADObject -Identity "CN=expiry,CN=Users,DC=magic,DC=local" -TargetPath "OU=test,OU=Sync,DC=magic,DC=local"
Even this command worked for me in my lab.
Do let me know if you have any further questions.
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