Hello,
Thank you for posting in Q&A forum.
To further check this issue, pleas kindly try below steps:
1.Please kindly check how you apply the GPO in your domain, is it pushed by GPO management or any other third-party platform like Intune?
2.After KB5020276 released for Windows update, you could encounter with such “An account with the same name exists in Active Directory. Re-using the account was blocked by security policy.” issue, for further details please kindly refer to below Microsoft Official Link:
REF:https://support.microsoft.com/en-us/topic/kb5020276-netjoin-domain-join-hardening-changes-2b65a0f3-1f4c-42ef-ac0f-1caaf421baf8
Best regards,
Jill Zhou
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