Hi @Melissa Lipinski - Thank you for reaching out to us. Happy to assist!
I understand trying to get the costs for your Azure development subscription. And also interested in getting the Actual Costs and Amortized Costs at Subscription level. Query API and Usage details API should match. So, you can use both.
Looking at the error for the Query API, seems like you are not using the right Request body. I suggest you to refer to this article for details - https://learn.microsoft.com/en-us/rest/api/cost-management/query/usage?tabs=HTTP
Hope this helps!
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