@Bharat Singh Thanks for reaching out. Microsoft.Azure.Management.ApiManagement NuGet package is obsolete as of September 30, 2023. It is no longer maintained or monitored. Microsoft encourages customers to upgrade to the replacement package, Azure.ResourceManager.ApiManagement, to continue receiving updates.
This change is likely causing the breaking changes you’re experiencing in your application that uses the ApiManagementClient from the Microsoft.Azure.Management.ApiManagement NuGet package.
For more information please refer: https://www.nuget.org/packages/Microsoft.Azure.Management.ApiManagement/
do let me know incase of further queries, I would be happy to assist you.
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