One important thing to note is that a conversation in Front can only contain messages of a specific "type" (i.e. messages sent/received via a certain channel type). This means that you can not import a message via a custom channel, and reply via an email channel.

I think the best solution in your case will be:

1. Visitor submits form. Your app processes it
2. Your app imports the submitted message into Front as an email via an email channel. Use the import message endpoint. 
3. In Front, you will respond from the channel the message was received on, to the visitor. 

I hope this is helpful - Please let me know if you have any further questions

--Jason

Hi there.
Can you help me with similar problem?
I created custom channel (email type) and try to import message using this endpoint but I got an error “404 Not found”. I can’t understand what is wrong (channel created, inbox created).
My goal - possibilities to reply for messages using Front.
If I use this endpoint I can add incoming messages into channel, but I can’t create replying
Thanks for advance

Hi Alex,

The 404 will refer to one of the resources specified in your request being not found. Note, you can specify the inbox_id, sender author_id (teammate ID), assignee_id and conversation_id (for threading).

If you’re still not sure where the issue is coming from, I’d suggest reaching out to our support team and sharing the exact API call you’re issuing (I wouldn’t recommend sharing that here as it may include some private details). Our support team will be able to offer more guidance on your specific case with access to the details of your API call.

Thanks