What's happening?
When a user from a specific business unit creates a customer journey, records from all business units are incorrectly entering the journey, despite each business unit being restricted to viewing only its own records.
Reason:
This occurs because the customer activated the feature switch for business units without reading the provided warning message. This feature, once enabled, cannot be disabled easily and affects how records are managed across business units. Additionally, the customer's contacts were confirmed to be located in the main business unit of the organization rather than in separate business units.
Resolution:
Ensure to review the documentation provided to understand the implications and expectations clearly before making changes. For outbound marketing this can be disabled by reviewing the steps listed in the following article: Business unit support in outbound marketing | Microsoft Learn
For real-time marketing, this feature cannot be disabled.
Business unit support in real-time journeys | Microsoft Learn
Enabling business unit scopes in Customer Insights - Journeys | Microsoft Learn