I think my Apple ID was hacked, changed my password twice but failed, what to do?
I recommend you contact Apple support immediately, and watch for any fraudulent purchases on the Apple Store and iTunes stores.

These links may be of help to you: https://support.apple.com/en-us/HT204145 (Apple support page for if you think your Apple ID has been compromised) and https://support.apple.com/contact (to contact Apple support).

Hope this helps!