As far as I can judge, a gambling addiction is of course not the fault of 1xbit. I don't think an accusation is in order there either. What I do wonder is what bets would these unfairly placed bets be from? Does the OP have a screenshot of that?
Wtf unfairly placed bets even mean?
If the casino thinks the bet is unfair, they shouldn't even let you bet on that game in the first place. If they are going to cancel bets because they think it was "unfair" then they shouldn't operate a casino. If a casino fails to make money even though mathematically the odds are in favor of the casino, it just means they suck at doing their job.
I don't think these words are about a single bet or an error in setting the odds.
From what my guess is, it's about some manipulation by creating multiaccounts and placing certain combinations of bets on them. I do not know how it looks like, but from a few explanations written by 1xBit support, I concluded something like that.
The mere creation of multiple accounts seems strange and suspicious to me, so all in all I'm not surprised that the casino often responds to this kind of behavior with an account lockout.