How did Pres. Trump get unanimous confirmation on Acting Secretary of Defense in Senate?

I am pleased to announce that Christopher C. Miller, the highly respected Director of the National Counterterrorism Center (unanimously confirmed by the Senate), will be Acting Secretary of Defense, effective immediately…..Chris will do a GREAT job! Mark Esper has been terminated. I would like to thank him for his service.

https://twitter.com/realDonaldTrump/status/1325859406349799424