Added note about scope format

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cc: @jmprieur

Author: MarileeTurscak-MSFT

articles/active-directory/develop/scenario-web-app-call-api-acquire-token.md

@@ -85,6 +85,9 @@ The code for ASP.NET is similar to the code shown for ASP.NET Core:
 - Finally, it calls the `AcquireTokenSilent` method of the confidential client application.
 - If interaction is required, the web app needs to challenge the user (re-sign in) and ask for more claims.
 
+>[!NOTE]
+>The scope should be the fully qualified scope name. For example,`({api_uri}/scope)`.
+
 The following code snippet is extracted from [HomeController.cs#L157-L192](https://github.com/Azure-Samples/ms-identity-aspnet-webapp-openidconnect/blob/257c8f96ec3ff875c351d1377b36403eed942a18/WebApp/Controllers/HomeController.cs#L157-L192) in the [ms-identity-aspnet-webapp-openidconnect](https://github.com/Azure-Samples/ms-identity-aspnet-webapp-openidconnect) ASP.NET MVC code sample:
 
 ```C#