Black clock screen not displaying (Sense 2)

[SamtheGroot]

My Fitbit is a Sense 2.

Before I changed my clock face to a Christmas one, I would have the 'always on display' on and if it didn't show the clock face, it would show white numbers (the time) on a black screen. I changed it to a Christmas one and it still had that. However, once I changed the clock face to the pre-Christmas one, it no longer shows the time on the black screen and wastes battery by showing the clock face screen. 

How can I change it to show the black and white time again? 

[JohnnyRow]

That depends somewhat on the clock face you have chosen.  Most of the clock faces, at least I think the ones 'by Fitbit" go to the time on black screen when 'always-on' display is chosen.  But I just realized some of the user-designed clock faces do have special 'always-on' displays similar to their full displays but without as much data.
I suspect you just are not using the same clock face as you had before changing to the Christmas one.