In accordance with Twilio's Messaging Policy, opt-in (user consent) is required when sending messages through Twilio's various channels and services.
For more information on what is considered proper consent, our requirements for obtaining consent, and how to maintain consent on an ongoing basis, please review Twilio's Messaging Policy.
Failure to obtain proper consent will result in blocks on your messaging traffic and impact your ability to continue messaging across your account(s). For more information on how to avoid message filtering please see How do I prevent my messages from being blocked?