Issue

Inbound SMS messages continue to create or append to active Twilio Conversations threads instead of executing the configured phone number webhook or Studio Flow.

Product

Conversations Classic

Environment

Twilio Console

Cause

This behavior occurs due to two main reasons:
 

1. Messaging Service Assignment: The phone number is assigned to a Messaging Service associated with the Conversations service (such as the "Default Messaging Service for Conversations").
    
2. Active Conversation Threads: An open conversation session still exists for the participant. Incoming messages from participants in an active conversation will continue to append to that open thread regardless of updated Messaging Service settings.

Resolution

To stop automatic conversation routing and restore standard webhook or Studio Flow execution:

Step 1: Remove the Phone Number from the Conversations Messaging Service

1. Log in to the Twilio Console.
2. Navigate to Messaging > Services and select the Messaging Service tied to Conversations.
3. Click Sender Pool from the left menu.
4. Locate the phone number, click Remove, and confirm the deletion.

Step 2: Close Existing Active Conversations via the API:

List all currently active conversation SIDs using the REST API:

curl -X GET "https://conversations.twilio.com/v1/Conversations?State=active" \
--user "YOUR_ACCOUNT_SID:YOUR_AUTH_TOKEN"

For each returned Conversation SID (CHxxxxxxxx...), update its state to closed:

curl -X POST "https://conversations.twilio.com/v1/Conversations/CHxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx" \
--data-urlencode "State=closed" \
--user "YOUR_ACCOUNT_SID:YOUR_AUTH_TOKEN"