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Fix capitalization and punctuation.

Author: AnnaMHuff

articles/communication-services/concepts/sms/opt-out-api-concept.md

@@ -26,4 +26,4 @@ Key features include:
 
 ## Next steps
 
-Let's get started with the [SMS Opt-out API quickstart](../../quickstarts/sms/opt-out-api-quickstart.md)
+Let's get started with the [SMS Opt-out API quickstart](../../quickstarts/sms/opt-out-api-quickstart.md).

articles/communication-services/quickstarts/sms/includes/sms-opt-out-api-javascript.md

@@ -24,7 +24,7 @@ Get started with Azure Communication Services SMS Opt-out API by using the follo
 
 ## Sample code to use Opt-Out API
 
-This sample demonstrates how to use the Opt-Out Management API in JavaScript to programmatically add, remove, or check opt-out entries
+This sample demonstrates how to use the Opt-Out Management API in JavaScript to programmatically add, remove, or check opt-out entries.
 
 ```html
 <script src="Scripts/CryptoJS/sha256-min.js" type="text/javascript"></script>

articles/communication-services/quickstarts/sms/opt-out-api-quickstart.md

@@ -130,7 +130,7 @@ In general, response contents are the same for all actions and contain the succe
 
 ## Next steps
 
-In this quickstart, you learned how to send OPt-out requests.
+In this quickstart, you learned how to send opt-out requests.
 
 > [!div class="nextstepaction"]
 > [Send an SMS message](./send.md)