Why was Kraken banned?

I'm quite surprised to hear that Kraken has been banned. As a cryptocurrency exchange with a reputation for being reliable and secure, it's unexpected to see it facing such a situation. Could you please elaborate on the reasons behind this ban? Was it due to some regulatory issues or was there a specific incident that triggered this decision? Also, what does this mean for the users of Kraken? Will they be able to access their funds or will they need to transfer their cryptocurrencies to another exchange? It would be helpful to have a clearer understanding of this situation.