This type of attack is called Credential Stuffing. This is a type of cyber attack in which an attacker gets your credentials from one service and attempts to log in to other unrelated services.
The main reason that credential stuffing attacks are effective is that 85% of people reuse passwords for most of their services.
Defending yourself against this type if attack is pretty straightforward. You should always use unique passwords for each service.
We recommend resetting your Alignable password to a strong unique password. We also recommend you update your email password to something unique as well.