If the customer does not respond to you then you are still obligated to arrive at the lesson. 

This is the commitment you made to both Teach Me 2 and to the customer when you confirmed and received the lesson schedule when you took the job. We, as Teach Me 2, require that you uphold that commitment and go to the lesson at the stipulated time today. You can use this session to assess where it is that the student is at, and how to proceed with the next lesson further.
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