Hi, @SliperPoon
Thank you for posting in Microsoft Q&A forum.
Do you have any secondary site in you hierarchy? The reason could be the primary server is upgraded to the latest version of the SCCM, but the secondary server is not upgraded. This is a supported scenario for Interoperability as per Microsoft documentation but not for CMPivot.
Once all sites are upgraded to the same version, you should be able to run CMPivot without any issues.
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