Sorry for the newbie question but I can't seem the figure this out. 
 

installed under cabinet snd in cabinet lighting in my kitchen and wetbar. I wanted a way to create an easy way for Alexa to turn on the mood lighting at night. 
 

so I grouped the 3-4 switches and called it Kitchen Lights. I also created a "Scene" for Alexa to recognize it. I can now turn them on. 
 

my question is...I can't figure out how to turn them off. Telling Alexa to turn off kitchen lights doesn't work ("doesn't support that"). Creating another scene with them defaulted to off and a different name didn't seem to work. 
 

can anyone help? All switches are dimmer switches.