Alexa problem! Empty Bearer Token

hey friends I am following this instruction: Everything works fine except that when I reached step 10, I saw a new window with empty bearer token and my raspberry pi can not process the signal spoken by me. I have been struggling with this issue for 3 days. Did anyone use alexa before? Can you show me what is the problem? I am very appreciated!

This is the openHAB forum - you are probably better off asking in a Rasperry Pi or Alexa forum.