Trusona uses Twilio to send SMS messages during the Trusonafication process. While performing a Trusonafication, you may encounter a situation where a user does not receive the SMS message. When this happens there are steps you can take to mitigate this behavior and further diagnose it:


1. Twilio is experiencing a service issue.

Please check https://status.twilio.com/ and ensure that SMS messaging for the specified carrier and location is green and not experiencing any degradation of service


2. The user is not subscribed to receive Twilio's messages

See https://www.twilio.com/docs/api/errors/21610 for more information. Users have the ability to re-subscribe to SMS messages by replying "Start" to an automated message.


3. Messages from Unknown Numbers are blocked

iOS: You will want to ensure that the user's phone settings are allowing SMS from unknown senders. See https://support.apple.com/guide/iphone/block-filter-and-report-messages-iph203ab0be4/ios for more information and steps.


Android:

  1. Open the messaging app: Locate and open your default messaging app (e.g., Google Messages, Samsung Messages). 
  2. Access settings: Find the settings menu within the app. This is often accessed by tapping the three dots (More) icon. 
  3. Locate "Blocked numbers" or "Spam & Blocked": The specific wording may vary by app, but you'll be looking for a section related to blocking or filtering messages. 
  4. Disable "Filter unknown senders" or similar: Turn off the feature that blocks messages from unknown numbers or numbers not in your contacts.