I interpreted using name would be used for referencing in automation. This way i can have multiple notifiers.
Either way, I also tried without adding name and still get the same error
name (Optional): Setting the optional parameter name allows multiple notifiers to be created. The default value is notify. The notifier will bind to the service notify.NOTIFIER_NAME.
When you look at the services dev tool, do you see a domain of “sms” and a service of “twilio_sms”? I’m betting: no. Twilio is a notification platform, so you should see something like “notify.twilio” (where twilio here is the name you gave it when setting up the platform - the token marked NOTIFIER_NAME in the platform example).