The article I linked outlines it pretty clearly.

"Cambridge Analytica then arranged an informed consent process for research in which several hundred thousand Facebook users would agree to complete a survey for payment that was only for academic use.[15][17] However, Facebook allowed this app not only to collect personal information from survey respondents but also from respondents' Facebook friends.[15] In this way, Cambridge Analytica acquired data from millions of Facebook users.[15]"

CA acquired access to the data of ~90 million users from the actions of several thousand other users whom they paid to fill out forms that stated they were for non-political use.

FB said data was private that they then shared with CA without user consent.

This was widely reported on, and people admitted to these behaviors. I am not sure an internal email is enough to rewrite history.

> If you read either my comment or the email, you'd know what the advice was.

I read both of these, and many of your recent comments seem to be some form of directed motivated reasoning or trolling, not sure.