You have created an API call that creates campaign lists and adds users, followed by the creation of content and initiation of the mailing. However, when executed, ListManager will only send the same message to the same user once when those messages are sent to multiple lists that the member is on and you want the member to receive all messages when cross-posted.
To allow the same message to be delivered to the same member use the UpdateList function in the API call with ListStruct as an argument. The ListStruct contains the following fields:
- AllowCrossPosting (boolean): If true, this list should accept cross-posted messages (identical messages sent to multiple lists)
- AllowDuplicatePosts (boolean): If true, this list should accept duplicate messages
Construction of the actual API call is beyond the scope of support. If you require custom programming assistance you can contact our Professional Services team for a quote to deliver your custom solution.