iTalki No-Show Policy Complaint After Missed Trial Class

There is an English-learning app called iTalki. Last week, I scheduled a lesson with a foreign teacher through the app to improve my English. I booked what they call a trial lesson (which, by the way, is not free) for 12:00 p.m. However, due to a busy schedule and weekday fatigue, I forgot about the appointment. No one sent a message, no one called, and there is no accessible customer service.