Attaches automation templates to an existing SMS campaign, including one that has already been sent.

Templates are added to the ones already on the campaign; nothing is replaced or removed. Templates of type "as-is" are linked to the campaign, and templates of type "duplicate" have their triggers, actions, and keywords copied onto it.

The request is safe to retry: a template that is already on the campaign is skipped, so its automations never run twice for the same reply.

Automations only run for replies received after they are attached. Contacts who replied earlier are not processed again. When possible, pass automation_templates when sending the campaign instead.

The campaign must have finished preprocessing and be in a draft, scheduled, queued, in_progress, paused or complete status. Every template must belong to the organization and must not be archived; otherwise nothing is attached.