Hi @Liem Nguyen ,
Welcome to Microsoft Q&A platform and thanks for using Azure services.
Regarding your question about API retirement, there were many questions raised by users in this forum.
Customers who have registered for Microsoft.SQL will receive these notifications, even though the customer did not create the Azure SQL DB they receive it due to the Microsft.SQL is registered for the subscription.
It is a general notification to existing SQL Database users to transition the new APIs by October 2025
Easiest way to get around this "issue" will be updating the SDK to a newer version (after mid of 2022)
There will be coming up more details on this retirement in the next few weeks Azure SQL Database REST API 2014-04-01 Retirement Notice
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