To create SMS Webhook, from the Main Menu, go to Settings -> Webhooks...
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Click on Create Webhook...
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Event: Select the event.
Type: Select SMS.
Description: Give your webhook a description.
Click Continue...
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Status: Select the Status. InActive Webhooks won't be executed.
Description: Give your webhook a description for your reference.
From: The from number. You must purchase a number. From the Main Menu go to Call Tracking -> Purchase Numbers
To: The number to send the SMS to (International Format)
Message: The Text message.