How does Opt-in and Opt-out work?
For Toll Free Numbers
When an end-user sends STOP (not case sensitive) from the handset, the carrier will send the STOP to the WEBTEXT gateway, which we pass to our customer. No further messages will be sent by the carrier however it is recommended the customer add this user to their own Do Not Call list.
The only way for a consumer to opt-in again after an opt-out, is to reply, sending the message "UNSTOP" to the number from which they opted out.
The consumer would have been given this information at the time of opt-out from the opt-out confirmation message sent by the carriers.
10DLC Numbers
Carriers do not automatically block outbound messages from the network when STOP is sent to 10DLC numbers. Customers need to maintain their own Do Not Call records for STOP messages received for these numbers or risk the number being blocked for SPAM.