Thanks for the Question and using Microsoft Q&A.
Have you opened Billing support ticket?
If not, please open Billing support ticket. Meanwhile please refer to the below Documents that might help you:
https://learn.microsoft.com/en-us/marketplace/refund-policies.
Please refer to this similar thread: https://learn.microsoft.com/en-us/answers/questions/1461649/i-need-a-refund-for-my-azure-subscriptions-i-accid
Hope this helps. Do let us know if you any further queries. If this answers your query, do click Accept Answer
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