Planet Spark — Non refund for unused classs

The company if expresses an interest will make a Google meet and announce classes and makes u pay for 100 classes in 1 go around 50000. After which they assign a teacher who is not at all regulat in taking classes. After 47 classes over 6 months while the entire courses should have been complete . Now on asking to discontinue they are stating that non refund possible After 5 classes. when I have nor got service hoe can they take charges for 53 classes.. some deduction is ok but almost 50% of the fees us toomich. they are saying they are assign a new teacher they do not monitor the progress of their teacher . nor advise as to why their teacher is not coming on time. How can such sites exist where such policies are placed