Buhari appointed new chairman 2017
I think there may be a small issue here.
As far as my knowledge goes, Muhammadu Buhari did not appoint a new chairman in 2017. In fact, the Chairman of the Economic and Financial Crimes Commission (EFCC) at that time was Ibrahim Magu, who was appointed by President Buhari in 2015.
If you could provide more context or clarify which chairman you are referring to, I'd be happy to help you with your question.