RERA will be applicable to such bookings and the rights of buyer are protected, only if the builder had not registered the project before the Act came into force.
Real Estate Regulatory Act, 2016 is a recent development and does not apply retrospectively. Application of RERA retrospectively is dependent upon registration and delivery of possession of project. Unlike DRT, there exists no provision for mandatory transfer of cases to RERA for adjudication.
However, you can file a case for cheating or fraud under Indian Penal Code, IPC with the help of best criminal lawyers in India since the builder defrauded you. You can also file a case for breach of contract and claim relief under Specific Relief Act, if the discrepancy and fraud can be proven with the help of a legal document.