title: I tried to run rasa shell i am getting ERROR asyncio Task exception was never retrieved future
body: <p>I am trying to develop simple chatbot using rasa framework when i run rasa shell to interact with chatbot ,it showing this error:</p>
  
  <pre><code>ERROR    asyncio  - Task exception was never retrieved
  future: &lt;Task finished coro=&lt;RestInput.on_message_wrapper() done, defined at /home/oretes/anaconda3/lib/python3.7/site-packages/rasa/core/channels/channel.py:392&gt; exception=ValueError('X.shape[1] = 256 should be equal to 128, the number of features at training time')&gt;
  
  ERROR    asyncio  - Task exception was never retrieved
  future: &lt;Task finished coro=&lt;RestInput.on_message_wrapper() done, defined at /home/oretes/anaconda3/lib/python3.7/site-packages/rasa/core/channels/channel.py:392&gt; exception=ValueError('X.shape[1] = 256 should be equal to 128, the number of features at training time')&gt;
  </code></pre>
  
  <p>I am trying to develop simple chatbot using rasa framework when i am running "rasa train" command is working correctly,after that i ran "rasa shell" to interact with chatbot,it is showing this error:ERROR Task exception was never retrieved future.</p>
  
  <p>i am using rasa framework</p>
  
  <p>I am trying to do normal conversation with chatbot that why i am running "rasa shell" command but when i say "hi" it showing error:ERROR Task exception was never retrieved future.</p>