Car parking allotment

Dear Sir, I bought a flat few years ago in Pune and got the possession of my flat in 2007. i shifted in the said flat in the year of 2012. at that point of time, i did not have any specific covered car parking allotted for my flat. but there used to be open common space where all (whoever did not have any specific car parking) used park their vehicle. Later (around an year back) my builder started allotting that space as well to flat owners as dedicated car parking for respective flats. When i approached my builder for allotting me also an specific place to park my car, he started asking me money for allotment. Over and above, there is no receipt for the same and probably a simple allotment letter. These parking (apart from cover parking) are made in common passage area (attached to boundary walls of society). These are open parking. Now when i refused to pay any additional amount for mere allotment of space to park my car, my builder refused to allot any space to me. To some flat owners, builder is allotting more than one parking. when i forced, he replied that there is no space left. Finally i approached my society committee to help me out in this but they refused by saying that they can not do any thing in this. Now the security guards are harassing me by putting jammer in my car if i park my vehicle by mistake to place allotted to some one else. My society is now threatening me that if i do not get specific place allotted to my flat, they would not allow my car to enter society and i have to park it out side. Kindly help.