Thanks for the question and using MS Q&A platform.
I understand that you are unable to create an Azure Synapse Workspace with the error code "WorkspaceInNonTerminalState" and the message "Workspace is in non-terminal state Failed and cannot be updated."
To resolve this issue, I suggest trying to deregister Microsoft SQL and then register it again before creating the Synapse Workspace. This may help in your case.
If the above solution does not help, it is possible that you have a stuck resource. As this is specific to your subscription, I would like to refer you to Azure support. They will be able to investigate and take the necessary action to resolve the issue.
If you do not have a support plan, please let us know so that we can help you with other options to unblock you.
Hope this helps. Do let us know if you any further queries.
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