Unable to add Operating System Upgrade Package under SCCM CB 2103

HI,

I am trying to add Operating System Upgrade package (Full Media extracted from ISO) in SCCM CB 2103. The ISO is for Windows 10 20H2 downloaded from Volume licensing from Microsoft. 

I have verified, that my SCCMADMIN account has all permission to the folder where this ISO has extracted. Also my Windows 10 ADK version is updated and supported for SCCM 2103.

The error message read as "The specified path does not contain a valid operating system or you do not have permission...."

Anyone knows about this issue?