Hi, @Loganathan R
Thank you for posting in Microsoft Q&A forum.
It seems SCCM can only upgrade from Windows 10 Pro to Windows 10 Enterprise instead of downgrade Windows 10 Enterprise to Pro edition.
For downgrade Windows 10 Enterprise to Pro edition, you may check this article to see if it helps:
https://www.minitool.com/backup-tips/downgrade-windows-10-enterprise-to-pro.html
(Please note: Information posted in the given link is hosted by a third party. Microsoft does not guarantee the accuracy and effectiveness of information.)
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