I am attempting to implement the API with Java. I was able to retrieve the authentication code using,  https://authz.constantcontact.com/oauth2/default/v1/authorize?client_id={your_client_id}&redirect_uri=https%3A%2F%2Flocalhost&response_type=code&scope=contact_data%20campaign_data%20offline_access&state=235o250eddsdff  but I have not have success retrieving the access token when using the authentication code from my redirected uri. I did use the code with 60 seconds like the solution that I saw.  ... View more