Their platform, that you must use, is glitchy and often does not work. You are not allowed to use another platform (under the guise of protecting teachers against fraud and abuse), so if the platform does not work you are expected to reschedule the lesson. Basically, you lose money because you are not paid for that lesson, and the students get annoyed because their lesson does not take place on the date and time they requested. When I argued this point after a student who was on a strict timescale was unable to access their platform, I received a highly insulting email form them. I withdrew my profile as a consequence. I over 20 years of teaching, I have never been treated so badly.