Setting Up the Facebook Messenger Channel

Facebook Messenger uses the same ecosystem as Instagram (Meta), but operates directly with Facebook Pages, without needing a linked Instagram account.

Prerequisites

• A Facebook Page (not a personal profile)
• Administrator access to the Page
• Hub Chatt2.me account with administrator permission on the Application

Connection process

1. Start authorization

In the Hub Chatt2.me dashboard:

1. Go to Channels → Activate/Configure → Messenger
2. Click Connect with Facebook

2. Authorize on Facebook

1. Log in with the Page administrator
2. Authorize the messaging permissions
3. Select the Facebook Page to be used as a channel

3. Channel ready

The channel UUID will be available in the details after the connection.

Identifying the recipient (to)

On Messenger, to is the PSID (Page-Scoped User ID) — the user's identifier in the context of your Page. It arrives via webhook when the user sends a message to the Page.

// Example webhook payload
{
  "sender": {
    "id": "26203292189261166"
  }
}

PSID vs IGSID

The PSID (Messenger) and the IGSID (Instagram) are different identifiers even if the user is the same person on Facebook. They are not interchangeable.

Differences from Instagram

Aspect	Messenger	Instagram
Identifier (to)	Page PSID	IGSID
Messaging window	24 hours	7 days
Stickers	Not supported	Supported
Documents	Supported as file attachment	Not supported for outbound sends
Mark as seen	Supported	Supported

Limitations

• Like Instagram, it is not possible to initiate conversations with users who have never interacted with the Page
• The messaging window is 24 hours after the user's last message
• Outside the window, Message Tags must be used (e.g. confirmed order notification) — consult Meta policies

Media formats and limits

Type	Formats maintained by the current Hub flow	Outbound limit	Inbound mirror limit
Image	JPEG, PNG, GIF, WebP	25 MB	Provider maximum not published; Hub safety ceiling 2 GiB
Audio	MP3/MPEG, M4A/MP4, OGG, WAV; WebM input is converted to M4A	25 MB	Provider maximum not published; Hub safety ceiling 2 GiB
Video	MP4 and WebM; QuickTime/MOV input is converted to H.264/AAC MP4	25 MB	Provider maximum not published; Hub safety ceiling 2 GiB
File	PDF, TXT, DOC/DOCX, PPT/PPTX, XLS/XLSX, ZIP	25 MB	Provider maximum not published; Hub safety ceiling 2 GiB

Messenger's Send API models these as image, audio, video, and file attachments. The Hub applies only the audio and video conversions listed above. Meta does not currently publish a stable exhaustive MIME matrix for this API, so the provider can still reject a file whose container or codec it cannot process. The inbound 2 GiB value is an operational download protection, not a Meta limit.

Identifying the sender (from)

In POST /v1/communication/messenger/message, set from to the application channel UUID or the Facebook Page ID for that channel (or the configured account id when applicable). The UUID always works as a fallback. See Sending messages overview.

Next steps

• Supported content types on Messenger
• Interactive messages — buttons, list, and CTA URL