@Richa Kumari Thank you for reaching out to us, As I understand you are trying to make changes to Microsoft Entra connect sync configuration (need to change OU).
Once you launch the Microsoft Entra Connect - Select Customize Synchronization options, you need to have either Global Administrator or Hybrid Identity Administrator privileges to change the OU configuration.
Same information has been mentioned on the wizard as well
Let me know if you have any further questions, feel free to post back.
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