Expired lessons

7 days ago
Hi everyone,
I have some students who would simply book a lesson(or a trial one) and then disappear for few months.
They wouldn't respond to scheduling requests even, so I wonder what happens then to the these expired lessons? Can teachers benefit from it?
Also, Is there a tool that could allow teachers to schedule lessons from their own end? It would be much easier to have such a tool, and save time as well.