With most chatbot channels, you can only send a broadcast message or notification to users who have interacted with your chatbot within the last 24 hours. Facebook one-time notifications allow users to opt-in to receive a single message on a specific topic after the 24-hour messaging window has elapsed. For example, you can invite users to opt-in to receive a single reminder about an upcoming event.
The message must be either a single text bubble or a button template, and uses a special token that allows it to be sent to the opted-in user. The token cannot be re-used: if you want to send that user an additional notification outside the usual messaging rules, you'll need to ask them to opt-in again.
For more information on Facebook's one-time notifications, see the Facebook help.
Plan your one-time notifications in advance
Users must opt-in to receive a one-time notification on the specific topic before you send the story. Make sure you give yourself enough time to create and publish the chatbot content that asks users to opt-in, and receive their opt-ins, before you want to send the story. A one-time notification opt-in is valid for one year from the time the user opts in.
To create a Facebook One-Time Notification, you'll need to: