The problem was that my posts were not visible to others, because my profile had been flagged (because I had used a disposable email).Then I put my real email, but nothing had changed. So I decided to cancel my registration (contacting the staff and explaining my decision). Instead of deleting, they fully restored my account, and everything was solved.
In my case I suspect I got caught by some anti-spam AI because hiding behind TOR when creating and using the account -- this effectively stops me from using this Microsoft service.