Once a number has successfully been claimed, the configuration for this number must be completed. If the 'EnableSMS' parameter has been set to 'Yes' in the Engage CloudFormation stack, then an SNS topic would have been created for SMS handling. This SNS topic must be specified as the topic to be used by Pinpoint. In order to apply this, navigate to Pinpoint and select 'Phone numbers'. A list of your SMS numbers will then be displayed.

 Select the SMS number, to be configured for SMS routing, by clicking on it.

Scroll down to the 'Two-way SMS' section and expand the section. Select 'Choose an existing SNS topic'. Select the SNS topic created by the Engage CloudFormation stack (it will contain the stack name as well as 'SMS') and click 'save' at the button of the page.

Note: A new SNS topic will be created each time a dual-stack upgrade is performed. Therefore, after each stack update, this setting must be modified to select the latest SNS topic.

Once this has been completed, ensure that the required Contact Flow routing has been configured, and that the SMS number has also been registered in Engage.

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