Pune : Open reserved parking issue after RERA law

I bought my flat in Pune in Dec 2017 through promoter & builder's focal person mentioned that the flat comes with open reserved parking. After buying my flat we did several follow-ups with builder and he mentioned that they will allocate it soon. Now builder wants to form society. When we raised our parking issues, this time he said he will not provide open reserved parking instead it will be open parking for all. This may due to builder have mentioned to RERA that there are 60 parking space (open + close) for 65 flats, whereas in reality actual marked parking slots are 43 ( open + close). When discussed this issue with builder, he said if we pay money then we can get open reserved parking even closed (which was not available while booking). 1. So builder asking money for open reserved parking is valid, when they mentioned its part of full package? 2. Can we file complaint against builder? What documents we need? 3. What legal steps we can take to resolve this? 4. Any easy solution?