Hello all,
We are posting some of the offline conversations on this topic, so that it is useful to other readers.
Scenario: Given that you last used the device in 2019, before the Azure Sphere GA date, it's possible that you have not migrated your tenant to the production system, therefor your device was not carried over. This is no-longer possible automatically. We can look to do this manually for you but need to establish proof-of-possession of both the device and tenant. Once the proof-of-possession is successful, you will hopefully have access to your tenant/device restored, otherwise unfortunately there won't be any further action we can take on this matter. Below details are needed to be provided to the Microsoft's Support Team to verify the proof-of-possession.
- The device ID
- The tenant ID
- User account identifiers such as email.
After looking into this issue, the product team were able to identify sufficient proof-of-ownership to restore access, the account should now be attached to the tenant as an administrator.
I hope this has resolved your issue.
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