@SC Lim I think in your case the issue is related to this thread.https://learn.microsoft.com/en-us/answers/questions/1983847/error-while-creating-a-managed-online-endpoint-in
Please try to follow the steps in the referenced thread and register the services in your subscription.
Steps -
Go to Azure Portal
Select your Subscription
Select Settings
Select Resource Providers
Make sure you add Microsoft.PolicyInsights and Microsoft.Cdn policies by selecting them and clicking the register button.
Refresh and retry the scenario from ML studio after some time.
If you still see the issue, please try to check if all the above registered services are also registered in your subscription. Thanks!!
If this answers your query, do click Accept Answer
and Yes
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