80901: Message Matched Stop Word

Proxy generated this warning because it did not forward an inbound SMS that matched a reserved opt-out keyword, or another opt-in or opt-out keyword that Proxy did not forward. By default, Proxy drops opt-out keywords instead of proxying them between participants. Dropped messages do not trigger callbacks.

• A participant sent a single-word opt-out keyword such as STOP, REVOKE, OPTOUT, UNSUBSCRIBE, END, CANCEL, QUIT, or STOPALL.
• A participant sent one of the French opt-out keywords that Proxy blocks, such as ARRETT, ARRET, or ARRETE.
• A participant sent UNSTOP, which Proxy does not forward even though Proxy forwards other opt-in, help, and info keywords between participants.
• Your application expected Proxy to forward one of these reserved keywords, but Proxy handled it before the message could be proxied.

• Ask participants not to send reserved opt-out keywords as standalone messages if the message should be delivered through Proxy.
• If the sender previously opted out and needs to receive messages from the Twilio number again, have them send START to opt back in.
• Design your workflow so you do not depend on callbacks for blocked opt-out messages. Proxy does not trigger callbacks for messages it drops.
• If you need custom handling for opt-in or opt-out keywords, contact Support to enable the ProxyRespectSmsStopFilterFlag account flag and then use InterceptCallbackUrl on your Proxy Service to apply your logic.

• Opt-out keywords
• Webhooks
• Twilio support for opt-out keywords (SMS STOP filtering)