Hsg Soc Share Certificate

Hello, Our residential complex falls under SRA plot. I bought a Flat in a Residential cum commercial tower in 2011. The builder was to give us the possession in the year 2013 however, he failed to do so. Finally he gave us the fit out letter in the year 2015. Still we have not received the possession letter or the OC for the building. However, the flat owners started to occupy the building and are staying in the building. The flat owners got to gather and made a Proposed Society and started to take care of the basic needs of the flat owners by collecting nominal maintenance. Now as the builder did not pay the property tax and other government dues we were not getting BMC water connection. It was collectively decided to collect 100/- per sq feet and pay the entire due tax liability. We received the water connection post payment of all dues on humanitarian grounds. As the builder had not completed the work we needed extra funds to finish the pending work of the building and make the premise habitable. Later it was decided that all members would volunteriarly make an additional contribution of 250/- per sq feet and this amount will be collected from the builder. However, as there were some members who did not want to take this additional burden. So when proposed society was formed they made this voluntary contribution as a compulsory contribution from the members and passed a resolution. Failing to make this payment they gave themselves the right to charge 18% interest under Proposed Society Maintenance Bill. I disputed this and have not made the contribution. Now we are a Cooperative Housing Society (without the OC or possession letter from the builder) and I still receive my maintenance bill with Arrears of the 250/- per sq feet unpad as principal amount and a cumulative Interest of 18% is levied on the same. Also, under the pretext of not paying the amount the society is not issuing me the share certificate. Since beginning I have been paying the maintenance on time and since the Cooperative Society is formed have also paid property tax on time and additional charges that the society has passed under the GBM or SGM or AGM from time to time. Am I under any obligation to pay the society this 250/- they are charging for getting the work done on builders behalf (builder has not given any such consent to the society)? Also, if the society is claiming the same amount from the builder with interest as per the audited accounts (incl 100/- paid in the beginning) is the hsg soc not claiming the same amount from 2 parties?