@Ben Levy Sorry for the painful experience.
I understand your concern about adding a new credit card (Canada) for using the subscription. You need to contact Azure billing and subscription management support to guide you adding a new credit card for the current subscription.
Please create a new billing support request using the instructions below.
Use this link to start the process:
https://portal.azure.com/#view/Microsoft_Azure_CostManagement/Menu/~/support/openedBy/AzurePortal
Fill out Summary, Problem type, Problem subtype, click Next. You will be prompted with some recommended solutions. Do not click on any of the recommended options shown.
In the upper left corner, click Return to support request
Click Next to move to Additional details tab, fill out required information, email/phone, etc., click Next, review details and submit case. After submitting you should receive an automated email with a few minutes and a support engineer should contact you within 1 business day.
FYI: Azure Billing and Subscription Management support is included in the Basic Support Plan without any charge.
https://azure.microsoft.com/en-us/support/plans/
Hope this helps. Please tag me in your reply if you have any concerns or need further assistance.
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