Merge pull request #185426 from MughundhanRaveendran-MSFT/patch-7

(AzureCXP) fixes MicrosoftDocs/azure-docs#86400

Author: PRMerger16

articles/azure-functions/functions-dotnet-dependency-injection.md

@@ -206,7 +206,7 @@ Overriding services provided by the host is currently not supported.  If there a
 
 Values defined in [app settings](./functions-how-to-use-azure-function-app-settings.md#settings) are available in an `IConfiguration` instance, which allows you to read app settings values in the startup class.
 
-You can extract values from the `IConfiguration` instance into a custom type. Copying the app settings values to a custom type makes it easy test your services by making these values injectable. Settings read into the configuration instance must be simple key/value pairs.
+You can extract values from the `IConfiguration` instance into a custom type. Copying the app settings values to a custom type makes it easy test your services by making these values injectable. Settings read into the configuration instance must be simple key/value pairs. Please note that, the functions running on Elastic Premium SKU has this constraint "App setting names can only contain letters, numbers (0-9), periods ("."), colons (":") and underscores ("_")"
 
 Consider the following class that includes a property named consistent with an app setting: