Charges for using resindential property for tuition classes

Hi Team, we are conducting tuition classes (nursery students) in our society from last 10 years. Earlier there was an objection on usage of premises for commercial purpose by some members. However, the matter was disregarded and we were allowed to operate. Understand that Society Bye laws of Maharashtra (MUMBAI) permits it. We have been paying extra maintenance of Rs. 600 pm as extra charges towards maintenance (last 2-3yrs). however, recently society has charged Rs. 50 per student, which has increased our cost enormously. There are other conducting tuition classes as well but with less students. We have more students and we are penalized. They don't consider the fixed cost attached to running a nursery. We use the premises only for 2 hrs. Whereas others use the premises for more time, though they have lesser students. The concept of per student charges are absurd in form of amenity charges. we don't mind paying charges. But it looks like a commission based activity and a burden on a nursery which is run on a household basis. is there any clause which helps us fight this wrong charges ?