To send text message to clients we must purchase a mobile number from Twilio console. Click on Buy “Buy a number number” from the Develop > Phone Numbers > Mnage side menu. If you don’t see it click on Explore products and click on the pin icon 
to add Phone Numbers to the sidebar.
Select the Country eg. Australia - AU. NOTE: New Zealand mobile number can not be purchased but instead purchase Australia mobile number.
Uncheck Voice, MMS, and Fax
Click Search
Click on Buy
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Voice Configuration: Delete the Webhook URL “https://demo.twilio.com/welcome/voice/”. This disables Twilio’s default voice message when the client calls back the number of text message received. Thus, it reduces the cost PD incurs.
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