The 'From' phone number provided is not a valid message-capable Twilio phone number for this destination/account
ERROR: 21606
PROGRAMMABLE SMS
ERROR
Description
You can only send SMS messages from a phone number, Alphanumeric Sender ID or short code provided by or ported to Twilio. Phone numbers must be SMS-capable. For Short Codes, the From number must be in the same country as the To number.
Visit the phone numbers page of your account portal to view a list of phone numbers that you own and to determine whether they are SMS-capable.
Possible Causes
The number you are using may not be capable of sending messages.
The number may be formatted incorrectly. Twilio accepts numbers in E.164 format.
If the number is a Short Code, it must be associated with the same country as the destination address.
The number you are using is in the process of porting/hosting.
The number you are using does not belong to the account whose credentials are present in the API request.
Possible Solutions
Check that you are using a Twilio phone number with SMS capabilities. You can see your purchased phone numbers and their capabilities in the Twilio console.
Ensure the number you are using is in E.164 format.
If you are sending from a Short Code, verify that the country you are sending to matches the country of the Short Code.
If you have ported/hosted the From number, ensure that the process is complete. You can follow up on this in the Twilio console for porting and hosting.
Check that you are using account credentials that correspond with the account that owns the phone number.