Changelly is a centralized exchange, which means it has an authority that controls and adheres to rules and laws and is responsible for the security of funds. Centralized exchanges charge a fee for their service.
However, customers don’t have as much responsibility in protecting their assets as those using a decentralized exchange. Centralized exchanges do run the risk of being hacked, but Changelly doesn’t hold funds for its customers, reducing the risk of cyberattacks.