Non issuence of documents required to take possession of flat

I have brought a flat numbered 305 in B M Silver Spring I have made complete payment barring 5 percent that I am expected to pay during or on or after taking possession of the said flat. The project B M Silver Spring is located in Trinity Homestead on Sarjapura Road, Domasandra post. In this regard I have to mention that I am I am getting any formal information from the builder that the flat is ready for possession neither I am being given the supporting document mentioning that the said property has been completed as had been agreed upon and and is ready for occupation. The flat was to be handed over on 31st August 15 with three month grace period (ended November 15) I have given them 4 months (ended March 16) extra from my side to complete the leftover work Still I am not given any information about the readiness of property for occupation. This is resulting me a loss of 10000 rs per month. I want the required documents provided to me from builder mentioning that the project has been completed as agreed upon and allow me to take possession of the property. Can you please suggest how should I proceed?