Hubspot API with REST connector

[pankaj999]

I am trying to connect to HubSpot API to generate an access token and then get the data. 

Problem is that when i paste the authorization code 1st time, it says connection successful but when I go into the connection and look for the access token , it says "BAD_AUTH_CODE"  and error 400 .

Every time I refresh the AUTH_CODE it gets connected but then when I am trying to open the data load to see the response it bumps me into the same error again. It's somehow gets expired very soon. Doesn't even shows the response.

I know the auth code and other parameters are right but somehow it's not working. Any ideas what could it be?

HubSpot API Doc

Thanks

Pankaj