Constant contact plugins – not working

Just installed constant contact but I’m not able to get it work. I’ve already registered to constantcontact.com as free trial(60 days).

I already configured the admin section using the username and password from constantcontact.com account. When I tried to add email in the front end I’m always getting message “Please try after some time!”, meaning it’s not successful. What I’ve done wrong? Any guys here had experienced with this issue?

Thanks a lot.