Layer mask not working?

I'm having the exact same problem. Hue/saturation adjustment mask isn't changing the color in the image I've selected. The only slider that works is the Lightness and it changes the part of the image from light grey to black, but the hue slider doesn't change the color at all.

I cannot fully understand what exactly you are trying to do but did you tried to add layer with color above your image then to change blend mode to Hue or Color and to play with Opacity?

It sounds like you might not be fully understanding how layer masks work.

You mention Hue/Sat for adding a colour cast.  That is the usual method of doing this, but did you tick Colorize?

Some screen captures of sample image whet you point out what you want to do and where would help. Layer mask are grayscale. A single selection channel.