Calling Common Module from Inbound Flow via Data Action

Trying to trigger a shared common flow from an inbound call flow using a Data Action. I’ve configured the action to call the endpoint /api/v2/architect/common-module-executions but it returns a 400 Bad Request. The JSON payload includes the correct commonModuleId and the caller’s contactId.

Here is the request body:
{“commonModuleId”: “12345”, “contactId”: “67890”}

The documentation says this should work for cross-flow reuse. Am I missing a required header or is the endpoint path different for inbound routing?