Possible Causes
Carrier has rejected for message length being invalid or too long. For messages destined to AT&T, messages with 10 segments or greater will be rejected.
Possible Solutions
Shorten the message to be within 10 segments
Is this billed?
Yes, this error is billed by the carriers
Are contacts that return this error marked as “invalid”?
No, contacts that return this error are not marked as “invalid” in your Textla contact list.