You must speak to your Alexa-enabled device to control your C by GE light switch.
When addressing your switch, you can say the name you assigned your switch or the name of the room / group your switches are in. You can choose alternate words for the same voice command: set / turn / make / switch / change / activate / deactivate.
Turn the Switch On / Off
"Alexa, turn <switch / group name> on / off."
"Alexa, turn on / off all switches."
Brighten / Dim the Lights
"Alexa, make <switch / group name> brighter / dimmer."
"Alexa, brighten / dim <switch / group name>."
"Alexa, brighten / dim <switch / group name> by <0% - 100%>."
"Alexa, brighten / dim <switch / group name> to <0% - 100%>."
"Alexa, turn up / down <switch / group name> to <0% - 100%>."
"Alexa, set <switch / group name> to <0% - 100%>."
"Alexa, increase / decrease <switch / group name>."