You don't need to add Alexa to a routine to control it with your voice - routines work with Alexa's voice commands after connecting Yonomi.
Each time you add a or change the name of a routine, you’ll need to refresh the Alexa integration by saying “Alexa, discover my devices.”
Wait for Alexa to finish discovering your changes, and then you're all set.
You can activate a routine by saying “Alexa, turn on <Routine Name>.”