Maintenance charges of flat purchased

Hi, Recently I purchased flat from builder which were ready to move. Society was formed of that building last 1 year. But I don't know builder paid the society maintenance charges or not as that flat was unsold. But now builder asking me to take NOC from managing committee of society which says no dues for that flat. And if their is any dues pending I have to pay that . According to me when I will take possession then only maintenance charges apply to me .so I want to confirm that whether I have to pay maintenance due if any pending to society or builder have to pay ? Also who will take NOC from society? My all remaining payment to builder done .because of only NOC from society , builder is not giving possession .please help. Actually flat which I bought is investor flat but my agreement done with builder . At the time of first meeting of deal, investor person told me that you have to pay society maintenance charges to society for one year in advance . He didn't mentioned that I have to pay dues . Regards, Vijay