Hacker started login into my accounts this week only and login in :-
1]paxful.com
2]poloniex.com
3]minergate.com
It started again this weekend after a gap in between.I am lucky that i had nil balance there and he only knows my common password.Though i had changed every accounts password .Now i am thinking to change my email as well and get accounts on all sites from starting.
I got the same emails from poloniex some time ago, but it do not get it again since I use 2FA on my poloniex account.
So maybe you can use it as well in order to keep your account safe from any hacker attempts.