@JohnSebastian-3934 Only images published by Canonical can be converted. Details can be found here. Can you confirm the VM SKU is one that is published by Canonical? If it is, please let me know the SKU details and region so I can further investigate. If it is a custom image or published by a third party you will need to migrate the VM to Ubuntu Pro by manually moving the data.
Hope this helps. Please let me know if you still have questions or run into more issues.
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