Messages can be blacklisted by carriers if the toll-free number formerly belonged to someone else. Please test the number once more by sending a message and let us know. If it still does not go through, we can change the number for you. Also, your purchased number may be blocked by a carrier if one of your recipients has contacted them stating they did not agree to receive messages from you. Please note that SMS messages should only be sent to clients that have previously opted into your services. Proof of opt-in may be required from us at any time if we are getting too many blocked messages.