Society's act is completely illegal
The advance maintenance paid by you to builder and having been transferred by him to society, should take care of your maintenance outgoings till the time the sum gets exhausted
Only thereafter you are liable to pay further maintenance charges
Society thus cannot compel you for second time and also withhold your share certificate
Please write to district deputy registrar of coop Societies complaining against the society act
If you dont get any response then you will have to file a dispute case in a co-operative court
You can first issue a legal notice to society and mark that letter to deputy registrar of coop society
Follow up with that letter by filing a RTI application if you don't get any response
Intimate society that you will recover all legal expenses from it due to the controversy created by it