title: Command ignored. Unknown target: undefined when using Ecommerce
body: <p>I am running into the below issue when trying to send transaction details. We are using Tag Manager to fire GA with a secondary tag for to fire transaction details. </p>
  
  <blockquote>
    <p>Executing Google Analytics commands.
    analytics_debug.js:10 Running command: ga("ecommerce:send")
    analytics_debug.js:10 Command ignored. 
    Unknown target: undefined</p>
  </blockquote>