Thank you for reaching out to the Microsoft Q&A platform. Happy to answer your question.
I understand from your question is that you want to cancel your Azure subscription. For that, you can refer to the below link to understand how it works.
https://learn.microsoft.com/en-us/azure/cost-management-billing/manage/cancel-azure-subscription
Any future promotion events, it can't be answered in the public forum. It's better if you create a support ticket from the portal. It's free.
https://learn.microsoft.com/en-us/azure/azure-portal/supportability/how-to-create-azure-support-request
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