@Eric Purdie
Thank you for reaching out.
I understand you need help with deleting and refund for Azure DDOS service.
DDoS protection plans cannot be deleted if they are associated with a virtual network. The first step is to disable the DDoS protection from a virtual network. You can follow the documentation here to disable the DDOS protection from VNET. After this step you need to delete the DDoS protection plan.
Please let me know if you face any issue in deletion.
Regarding refund, as this issue is related to billing of a resource, the correct approach here will be to create a Billing Support Ticket with Azure. Azure provides free billing support to all Azure customers. You can follow the documentation here and create a support ticket of type Billing.
Please let me know if you have any additional questions. Thank you!
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