I think you are getting it wrong. Getting fixed matches is not that the the team that is involved decided to allow their opponent to win the bet because they are paid for it. Making prediction sites and communities do use the word fixed matches because they believe many gamblers would want to subscribe to their channels because they will think that they will win many of the prediction matches.
I have bet on many fixed matches and I won some and lost many of the bets. Nothing like fixed matches when it comes to predictions.
All those prediction sites and punters who use the term "fixed matches" to market their services are scammers because when you say a match is fixed, it means the result has been scripted. I don't know if the players, club, or match officials are in on it, but it means the result is scripted. It either ends in a draw or a win for either team.
You can't use "fixed matches " for a match you just predicted.
This shows that anybody who says he has a fixed match is a scam. I don't believe in fixed matches. Not like I don't believe that there are fixed matches, but it's usually for very low leagues and anybody that has that information will not televise it for the world to see. He'll quietly stake and take his profit because it's illegal. If he wants to share it would be with a close circle.
So what you played and won was just a normal prediction by somebody and that is why you won some and lost some because that's how gambling is.