Hello @Zengxi Wang Thank you for reaching out to us on Microsoft Q&A platform and I apologize for the inconvenience this must have caused you!
Based on the information provided, I understand that you created an Azure Key Vault by mistake and deleted it the same day. However, you noticed huge cost influx for the said service.
I recommend you raise a refund request by creating a support request to Azure billing team. The ticket enables you to work closely with the support engineers and get a quick resolution to your issue.
FYI: Azure Billing and Subscription Management support is included in the Basic Support Plan without any charge.
https://azure.microsoft.com/en-us/support/plans/
Please carefully follow the instructions below and add a comment below with your results. If it doesn't allow you to open the case please describe what happened and I'll assist you. I've had people do this many times with success.
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. There is no charge for billing/subscription management support requests. A support engineer will assist you with your refund request.
Just for your information:
Azure Key Vault is priced based on the number of operations performed on the keys, secrets, and certificates stored in the vault. The pricing is based on the number of transactions, which includes operations such as creating, reading, updating, and deleting keys, secrets, and certificates.
Azure Key Vault has two pricing tiers: Standard and Premium. The Standard tier is designed for most common scenarios and provides a cost-effective solution for managing keys, secrets, and certificates. The Premium tier is designed for customers who require FIPS 140-2 Level 2 validated HSMs and want to use Azure Dedicated HSMs or Azure Private Link.
In addition to the transactional pricing, there are also charges for storing keys, secrets, and certificates in the vault. The storage charges are based on the number of objects stored in the vault and the amount of data stored.
For more information on Azure Key Vault pricing, including transactional pricing, storage pricing, and pricing for the Premium tier, please refer to the Azure Key Vault pricing page: https://azure.microsoft.com/pricing/details/key-vault/
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