I booked a trial lesson with a tutor. A day before the class, she changed the date and time without my permission. After the trial lesson, she said she would send me some homework. I then booked a second lesson. As the lesson approached and I still hadn't received my homework, I asked her twice, but she pretended not to have read my messages. Once again, she rescheduled the lesson without consulting me first. Since I had not received the homework, I cancelled the lesson. The next time I checked, she appeared as "not available." Preply refused to refund the trial class, even though I didn't learn anything and the tutor did not fulfil her duties. They also tie you up with their subscription plans.Edited to add: Do not believe anything they say in their reply. I've contacted them; once they grab your money they won't it let go.