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Twilio Error 21416: The 'From' phone number is not a valid international number.
Understanding Twilio and Its Purpose
Twilio is a cloud communications platform that enables developers to build, scale, and operate real-time communications within their software applications. It provides APIs for SMS, voice, video, and other communication channels, allowing seamless integration into applications.
Identifying the Symptom: Error 21416
When using Twilio's SMS API, you might encounter the error code 21416. This error indicates that the 'From' phone number specified in your API request is not recognized as a valid international number.
What You Observe
Upon sending an SMS through Twilio, the request fails, and you receive an error message similar to: 'Error 21416: The 'From' phone number is not a valid international number.'
Explaining the Issue: Error 21416
This error typically arises when the phone number used in the 'From' field of your API request is not in the correct format or is not a number purchased from Twilio. Twilio requires phone numbers to be in the E.164 format, which includes the country code and omits any unnecessary characters like dashes or spaces.
Common Causes
- The phone number is not in E.164 format.
- The phone number is not a Twilio number.
- Incorrect country code or missing digits.
Steps to Fix Error 21416
To resolve this issue, follow these steps:
Step 1: Verify the Phone Number Format
Ensure that the 'From' phone number is in E.164 format. This format includes the '+' sign, followed by the country code and the subscriber number. For example, a US number should look like +14155552671.
Step 2: Use a Valid Twilio Number
Make sure the 'From' number is a Twilio number. You can purchase a Twilio number from the Twilio Console. Once purchased, use this number in your API requests.
Step 3: Update Your API Request
After verifying the format and ensuring the number is a Twilio number, update your API request with the correct 'From' number. Here is an example of how to format your request:
{
"From": "+14155552671",
"To": "+1234567890",
"Body": "Hello, this is a test message!"
}
Conclusion
By ensuring that your 'From' phone number is in the correct format and is a valid Twilio number, you can resolve Error 21416 and successfully send SMS messages using Twilio's API. For further assistance, refer to the Twilio Error Code Documentation.
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Twilio Error 21416: The 'From' phone number is not a valid international number.
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