On January 3rd, President Trump sent a nomination withdrawal to the Senate for Acting Secretary of Homeland Security, Chad F. Wolf. Wolf has been Acting Secretary of DHS since November 13, 2019 and was appointed by President Trump.
Source of Information:
Whitehouse (Whitehouse.gov), 1/7/21, NOMINATIONS & APPOINTMENTS:
Homeland Security (DHS.gov), 5/18/20, Leadership: