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When Meta refuses to send a Messenger or Instagram message, the Inbox keeps it in the conversation, marked Not delivered, with one of the sentences below under it and a What to do link to the matching section. The person did not get it.
WhatsApp has its own list: WhatsApp error messages, decoded.
| What we show you | Meta's code | What it means | What to do |
|---|---|---|---|
| Messenger (or Instagram) only allows a reply within 24 hours | 10, subcode 2018278, 2534022 or 2018065 | The person last wrote more than 24 hours ago | Nothing to fix. They get your next reply as soon as they write in again |
| This person isn't receiving messages right now | 551, or 200 / 10 / 100 with a "person unavailable" subcode | Blocked, restricted who can message them, or account gone | Nothing to fix on your side |
| This connection is not allowed to send messages | 200, 10 | The login did not grant messaging, or the app lost it | Reconnect the channel and grant every permission |
| This Instagram account does not let connected apps send its messages | 200, subcode 2534041 | Message access for connected tools is off in Instagram | Turn it on in the Instagram app |
| The access token was rejected | 190, or HTTP 401 | The token expired or was revoked | Reconnect the channel |
| Meta is rate-limiting this account | 4, 613, or HTTP 429 | Too many requests too quickly | Wait a minute. Nothing is broken |
| Meta's API is not responding | any 5xx, or 2 | Their side | Try again in a few minutes |
| Messenger (or Instagram) refused to send this message | anything else | An error we have not mapped | Check the connection; tell us the exact wording if it keeps happening |
The 24-hour window has closed
Messenger and Instagram allow a reply for 24 hours after a person's last message. After that Meta refuses ordinary replies, and FiguredOutAI does not send the tagged messages Meta allows outside the window: they are reserved for narrow cases and misusing them can get a Page restricted. Nothing is wrong with your connection. When the person writes again, your next reply goes through. Follow-ups already respect the window and are skipped rather than refused — why a follow-up was not sent.
The person is not receiving messages
Meta could not reach this one person. They may have blocked your Page or Instagram account, limited who can message them, or deactivated their account. Other conversations are unaffected, and there is nothing to change in FiguredOutAI.
The connection cannot send messages
The connection is valid but is not allowed to message people. Usually the login that connected it did not grant every permission, or someone removed the app's access in the Page's or account's settings afterwards. Reconnect the channel from Configuration → Channels and accept every permission Meta asks for.
On Instagram there is one more switch. In the Instagram app, open Settings → Messages and story replies → Message controls → Connected tools and turn on Allow access to messages. With it off, Meta refuses every send from a connected app.
The access token was rejected
The token stored for this channel no longer works: it expired, someone changed the account's password, or the app was removed. The channel card shows the connection as not working. Reconnect it from Configuration → Channels.
Meta is rate-limiting you
Too many messages in a short time. Wait a minute; nothing is lost, and later messages go through.
Something else
If Meta answered 5xx, it is their side and it passes. For anything else, check the channel on Configuration → Channels. If the same message keeps coming back, tell us the exact wording: an unmapped Meta code is something we want to add to this page.