This is actually something which has been circling the web recently as there have been pretty big sites in the last few months to a year which have been exposed recently with full credentials being populated on the dark web and individuals using the same credentials frequently, has caused lots of problems with spammers getting into otherwise dormant or trustworthy users. As mentioned, we recommend enabling 2FA if you're concerned about your users.
I am sorry you feel we do not care, it is actually the opposite which we are providing you this information about how to better secure user accounts. With the limited information of the same IP address we were provided, we are providing the results of what we have seen previously. This is nothing new and ultimately, not seeing this come from an exploit of our software. If there is new information which is showing that the account has been compromised through the software, we will certainly investigate that but at this time, there is no evidence of that.
This would point further to exploited credentials, I'm afraid.