Thanks for your detailed response, the error details provide some clues, it seem you have not registered you provider, please try below steps -
You can see the registration status and register a resource provider namespace through the portal.
- Sign in to Azure portal.
- In the search box, enter subscriptions. Or if you've recently viewed your subscription, select Subscriptions.
- Select the subscription you want to use to register a resource provider.
- To see the list of resource providers, under Settings select Resource providers.
- To register a resource provider, select the resource provider and then select Register.
- I will suggest your register Microsoft.PolicyInsights as well.
Please have a try and let us know how it works. I hope it helps.
Regards,
Yutong
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