NBFC Violated the regulator guideline and approved project

I was allotted a flat in one of the project in Gurgaon by a private builder under affordable housing policy government of Haryana 2013. For the finance builder informed that one of the NBFC is approving the loan for this project so I took loan from them. But after 6 years flat not delivered and I was paying high interest to NBFC so I made balance amount payment and close the loan. Later though National housing bank website I came to know that NBFC can not approved a project with time linked payment plan and only construction linked plan can be financed but this NBFC did not followed the guideline and did disbursal.This whole things looks like a clear violation of fare banking practice due to which we innocent customer got stuck with such builders. If they do not finance we will not buy we trusted that such big NBFC is approving the project so things should be ok and project also under license of Haryana government.I want to file a case against this NBFC what is the correct way.