hello,this happened two times during 2 months or less ,
my root password changed ! although activating two auth verification !
and then i should tell the data center to change the root password ! is there any hack or anything happen ! the server is stable and have a lot of VPS ( windows and linux ) , i don't know what is going on !
There are a lot possibilities how someone can attack your server and change root password, specially over ssh. There is no such thing as 2FA for this. Even if you protect the root account with 2FA in VIRTUALIZOR does not mean it is protected when used for ssh access.
Take the well known measures for protecting root access (setting up ssh keys and disable password authentication for example)
If your password has been changed twice in short time your server for sure is compromised with a backdoor shell or similiar, so you should run commercial grade security software like ESET File Security on your server.