@Alistair Stam-Boelijn Thank you for reaching out to us through Microsoft Q&A platform. Happy to assist!
From the details posted, I understand that you want to raise refund request for one of the invoices of your subscription that isn't in use and unable to raise a support request.
Sorry for the inconvenience this must have caused you. Please create a New Support Request in the portal and choose Issue type: Billing Problem type: Refund request, then click Next. Once it shows suggested solutions, DO NOT CLICK the Request a refund button, click Return to support request in upper left corner as shown below:
Click Next, continue filling out information, make sure your email/phone are correct, and finishing creating the case.
If you are unable to create a support request, I suggest you try the following options:
Twitter : Connect with @AzureSupport on Twitter for answers, support, and to connect with Azure experts. best place to raise a request
Few Customers are using the Microsoft REST API Support Tickets - REST API (Azure Support) | Microsoft Learn to create Support request.
OR
You can call global customer service - https://support.microsoft.com/en-gb/topic/global-customer-service-phone-numbers-c0389ade-5640-e588-8b0e-28de8afeb3f2 to raise a support request on your behalf to help you connect with Azure billing and subscription management support.
Hope this helps!
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