ONTAP upgrade pre-check validation fails with Error: The following nodes are not supported

ONTAP 9

Validation checks for ONTAP upgrade, pre-checks fail with error:

cluster::> cluster image validate -version 9.X.X

It can take several minutes to complete validation...

WARNING: There are additional manual upgrade validation checks that must be performed after these automated validation 
checks have completed successfully. 
Refer to the Upgrade Advisor Plan or the "What should I verify before I upgrade with or without Upgrade Advisor" section 
in the "Upgrade ONTAP" documentation for the remaining manual validation checks that need to be performed before update. 
Upgrade ONTAP documentation available at: https://docs.netapp.com/us-en/ontap/upgrade/index.html 
The list of checks are available at: https://docs.netapp.com/us-en/ontap/upgrade/task_what_to_check_before_upgrade.html
Failing to do so can result in an update failure or an I/O disruption.
Please use Interoperability Matrix Tool (IMT  http://mysupport.netapp.com/matrix) to verify host system supportability 
configuration information.

Validation checks started successfully.  Run the "cluster image show-update-progress" command to check validation status.

cluster::> cluster image show-update-progress

Update Phase         Status                   Duration        Duration
-------------------- ----------------- --------------- ---------------
Pre-update checks    failed                   00:10:00        00:01:03

Details:

Pre-update Check     Status            Error-Action
-------------------- ----------------- --------------------------------------
Platform status      Error             Error: The following nodes are not
supported: Node1 (AFF-A200), Node2
(AFF-A200).
Action: Use the "cluster unjoin"
command to remove the unsupported
system from the cluster or upgrade
the controller hardware before
installing the new software release.