So probably it's not the API, since it exhausted some of my daily calls. It's probably some settings issue.
Anyway, I forgot to add that I have one more license of SC3 and it works. However, the license associated with this account does not work. I need this account too since my agency uses multiple accounts.
Here's the screenshot of my API settings: http://prntscr.com/cwiedi
I use the ultimate spin settings. When I create a project in SCM, the article is not spinned.
Here's what SCM generates (all looks good): http://prntscr.com/cwif0l
Please note that I'm experienced user of SCM as I have used many spinners as well.