@Giles Matthews - Welcome to Microsoft Q&A and thanks for reaching out to us.
I apologize for the inconvenience you’re facing. To reset the subscription creation process in Azure,
You can first Cancel the subscription that is created. After cancellation, Microsoft waits 30 to 90 days before permanently deleting your data in case you need to access it or recover your data.
Wait for 7 days after canceling the subscription. The “Delete subscription” option will become available in the Azure portal, then you can delete the Azure subscription that you created and start the process again
Hope this helps. and please feel free to reach out if you have any further questions.
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