My account has been hacked and I can't access it anymore


It’s absurd. My account @nonsapeviche (90.000 followers) has been hacked, the hackers changed email and password, and when I fill the form on, they answer (MrReyes) me that the email from where I write, is not the email associated with the account. I KNOW, THE HACKERS CHANGED THE EMAIL of the account. How is possible that a social network like Twitter works like this?
I want to specify also, that I wanted to secure my account with the telephone number confirmation, but the service is still not available in Italy.
We spent a lot of money (we write 30 original contents everyday) to grow the account, and what happened is a shame.