After importing an Azure Function app into API Management service, how do I view/edit the policy adding the generated host key authorizing calls?

I would start with checking Effective policy view to check if it’s added by the policy. I’m guessing this is the case.

Select All operations or any operation, select the code view for policies and then select “calculate effective policy”, this should show all the policies related to that operations.

I’m guessing that’s either API level policy or Product level. Product policies can be checked and changed from Products-view and API lelve from “All operations” -level. There are also global policies but I don’t think tis’ there.