Lightroom Mobile - Greyscale color edits not saving to preset

Hi! First time poster so be patient with me...

I'm trying to save my b&w edit as a preset in the Lightroom app, but any color edits I've made aren't saved when I apply the preset to another photo. For instance, the temp, tint & blue luminance should all be tweaked, but are all at zero when I apply the edit. Is this because it's a monochromatic color profile? All of the boxes are ticked on the "new preset" page except Optics, Geometry and Tools.

Any advice appreciated!