Configuring Amazon skill management API with Kong gateway - fails

I am trying to configure the Amazon’s Skill management API(SMAPI. RESTful) to kong gateway. And it fails.
However. the direct curl call to the SMAPI works without any issue.

More info:
OS : Ubuntu 18
Kong version : 0.14.1
I am under a corporate network and the system proxy is set(Note : direct curl call works).

Below is the error that i get,

*   Trying ::1...
* connect to ::1 port 8000 failed: Connection refused
*   Trying
* Connected to localhost ( port 8000 (#0)
> GET /v1/vendors HTTP/1.1
> User-Agent: curl/7.58.0
> Accept: */*
< HTTP/1.1 500 Internal Server Error
HTTP/1.1 500 Internal Server Error
< Date: Thu, 20 Sep 2018 11:24:14 GMT
Date: Thu, 20 Sep 2018 11:24:14 GMT
< Content-Type: application/json; charset=utf-8
Content-Type: application/json; charset=utf-8
< Connection: keep-alive
Connection: keep-alive
< Server: kong/0.14.1
Server: kong/0.14.1
< Content-Length: 43
Content-Length: 43

{"message":"An unexpected error occurred"}
* Connection #0 to host localhost left intact

I followed the kong document in this link to add the service,

curl -i -X POST \
  --url http://localhost:8001/services/ \
  --data 'name=alexa-service' \
  --data 'url='

Added the route.

  curl -i -X POST \
  --url http://localhost:8001/services/alexa-service/routes \
  --data 'hosts[]' \
  --data 'preserve_host=true'

I have tried making the preserve_host:false as well. No luck!
Calling the API,

curl -i -X GET
–url http://localhost:8000/
–header ‘Host:

Note : The configuration of the http://mockbin as given in the kong doc also fails. Let me know if i am missing something.

Perhaps requires ?

Some more knowledgeable hopefully responds, but AFAIK this seems to be the only way to get Kong working behind a corporate proxy.