@Prajith Karumathil You need to disable Directory Synchronization for the tenant. Use below PowerShell cmdlets for this purpose:
- Run
Install-Module MSOnline
. (If the module is not already installed). - Run
Connect-MsolService
and login via Global Admin account of your tenant. - Run
Set-MsolDirSyncEnabled -EnableDirSync $false
to disable Directory Synchronization.
Once it is disabled, you should be able to delete the synced accounts.
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