Hello
Thank you for your question and reaching out.
I can understand you are having some issues related to Ad users when created Date incorrect result.
Please try launch AD powershell from a DC or remote server admin tools and run the following command with elevated mode.
Get-ADUser -filter * -Properties samAccountName,WhenCreated | Select-Object samAccountName,WhenCreated
Also , please ensure AD replication is good in health and all are synced.
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