Participant attributes missing in Architect inbound message data action

I’ve got a custom web messaging channel running through DFO. When a user sends a message, I’m setting custom attributes on the participant via the Conversations API before the flow processes it.

Here’s the payload I’m sending to /api/v2/conversations/messages/{conversationId}/participants/{participantId}:

{
 "attributes": {
 "customTier": "platinum",
 "sessionId": "sess-998877"
 }
}

The API returns 204 No Content, which is expected. I can verify the attributes are attached to the participant object in the Genesys UI.

The problem is inside the Architect flow. I have an Inbound Message flow trigger. When it hits a Data Action to send data to our backend, the customTier and sessionId attributes aren’t showing up in the participant context.

I’m using the standard {{participant.attributes.customTier}} syntax in the Data Action mapping. It comes back null.

I’ve checked the timestamp. The API call happens 2 seconds before the flow processes the message. Is there a delay in how Architect caches participant attributes for web messaging? Or do I need to pull the attributes via a separate Get Participant action inside the flow instead of relying on the trigger context?

This works fine for voice calls, but web messaging seems to lag on the attribute propagation.