undefined method `account' for Twilio

I am using twilio and get: error undefined method `account' for Twilio.

    client = Twilio::REST::Client.new('twilio_sid','twilio_token')
    # Create and send an SMS message
    client.account.sms.messages.create(
    from: "+12345678901",
    to: user.contact,
    body: "Thanks for signing up. To verify your account, please reply HELLO to this message."
)