A good way to look at it is if a person had a 10 team multi. If the last game gets cancelled by the book or any other reason, it doesn't wipe out those 9 wins. Every book would cancel the last bet if that were the case.
Yes, you are right if you look at that way but here this did not happen. They cancelled the whole slip if I am not wrong.
That's exactly what happened. They canceled all my slips. Some of them already had 3/4 winners, waiting for the 4th game to be played.
Uhh... OP, dplay, help me understand, walk me through your shoes and help me see through your eyes, how did you place your bets? Why do you think, in your wildest imagination [and please be fair on this], that the casino considered your betting preference as something worth flagged?
I am not accusing you, nor trying to find a way to invalidate your dispute [in case that idea ever crossed anyone's mind], I am trying to understand your situation immersively, so I can be "you" and see if the casino's call is justified and/or what to say as rebuttal.
I mean you all see my bets, all of them are on big leagues, all parleys (up to 10 legs). I've been with them for maybe about a year at that point, and I've pretty much gambled the same way throughout. If there's any merit to them flagging my account, I'm sure they'd be quite vocal about it and point out in which ways I've been an unfair player, but they have nothing.
I've had quite a nice streak and won quite a bit of money in the couple of months prior to the bets cancellation, in those situations the sportsbook are tempted to do something about your account. It's a fairly common business model, just confiscate the cash of your biggest winners and it becomes quite easy to run a profitable shop.