Nightshift turning off after waking from sleep
I've got a new 2019 16-inch Macbook Pro running the latest version of Catalina (10.15.2). I have Nightshift enabled all the time. I set the schedule to be on from 7am - 11pm. However, when I lock my screen/the laptop goes to sleep and I come back, Nightshift "turns off". I have to go into System Preference and move the slider to reactivate it.
Also, if this makes any difference, I have an external monitor connected.
Any thoughts?
MacBook Pro 16", macOS 10.15