Discussion Board for collaboration related to Qlik Education.
This is a Circular Reference warning.
Reading this article will clarify what a Circular Reference is:
If you search for Circular Reference in the QlikCommunity, you'll find more information about what should you do in order to eliminate the circular references from your data model.
Maybe you should try working a bit more on your data model so as to eliminate the synthetic keys as well as the circular reference.