Hi @amadou diallo ,
Welcome to the Microsoft Q&A Platform! Thank you for asking your question here.
We understand from your query, it appears you're encountering an issue with syncing users from M365 to on-prem AD.
I'm sorry, but there isn't a way to sync users back to your on-premises Active Directory from Microsoft 365. The sync process only works from your on-premises Active Directory to Microsoft 365.
I would suggest you post this idea at the Azure Feedback Portal, which is monitored by the product team for feature enhancements.
If you have any further queries, do let us know.
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