1) if police is not taking any action on your complaint not registering any FIR you have to file complaint befit magistrate under section 156 (3)to direct cops to investigate and submit report
2) you appear to be bonafide purchaser of value you have parted with rs 7 lakhs on basis of agreement of sale and have registered your sale deed
3) the fact on discovery of fraud you have lodged police complaint proves your bonafide .i do hope you had taken written opinion of advocates that title is clear and marketable
4) you will get anticipatory bail
5) rely upon opinion obtained by you from advocates to prove your innocence
6) for recovery of your money you have to file a civil suit . Do it after filing criminal complaint of cheating criminal breach of trust forgery against the fraudster