Because as you play some of the games, it builds up a meter that can trigger the bonus. This meter stays at the level you have built during each session. So when they changed provider this progress was reset to 0.
so here is just another complaint about not winning a potential bonus. I believe that everyone knows that bonuses are not an obligation of any casino, and they create them at will and cancel them when they want or think they are no longer needed.
OP, unfortunately for you, there are no elements of fraud here. you can only pretend that this casino is not fair and they don't have bonuses worth paying attention to.
It’s not that kind of bonus, it was a bonus built in to the slot and the slot remembered the progress. The slot has been rebranded and the bonus works the same just everyone’s progress was reset.