For clarification for those who don't know, a new event system was recently implemented (that was not announced of course) where if you already have the hat that is being hosted, then you cannot enter the warper.
As an experienced eventer for a few years now, I can confirm everything what reggie said above as true. My two favorite things to do on graal are competing in events and towering. Everything else is boring to me. I'm at the point now where I have a decent amount of event hats almost at 60. I understand that there are greedy people who win events even when they already have the hat. But from what I've seen from my time in the event community, that's not extremely common. Most people are generous enough to let someone else win. And even if that is not the case, I believe everyone should be able to compete in events even if they have the hat. Immediately warping someone when they use their experience and memory to find warpers and not allowing them to have fun (competing in the event) just removes 1 out of 2 things that I enjoy doing on this game. I can no longer enjoy playing events as I have before. I'm limited in the amount of events that I can do. This system does bring about a positive change of allowing newer players a chance to win event hats but I feel that it has more negatives as more experienced players who have enjoyed doing events for a long time can no longer compete in them and eventually leads to people wanting to quit because they can no longer do one of the few activities that they find fun doing on graal.
Also, there's one more thing. This new system is incredible buggy and seems like it was rushed out. At first, I entered a warper where I already had the hat just to verify the new system. But now, I have entered around 3 warpers that I know are real and where I do not have the hat for and I get warped each time. I've even tried entering on my alternate accounts and it does not work. Please just revert it back to the old system. Hardly anyone complained in the first place and there are other systems that people have been wanting that are not events. Leave events alone. Focus on other parts of the game.