Related recruitment ongc

Sir Sir I had attended ONGC interview on [deleted] for the post of Geophysicist (surface), At the time of interview they asked me for NOC(No objection Certificate) because on [deleted] i have joined Geological Survey of India(GSI) on temporary basis, But As per ONGC Recruitment Policy “ If candidate is employed in Govt./Quasi Govt./PSU on the last date of application then NOC(No objection Certificate) is required”. Since I am not employed in Govt./Quasi Govt./PSU service on the last date of application and joined GSI before two days of interview, then in my case NOC is not required. so why they asked me NOC. And my second point is that , Instead of NOC they have taken Undertaking and in undertaking I had written that In case of my final selection I will produce NOC, Why they not declare my result ( but as per above paragraph this undertaking is not required) On [deleted] I got one mail from ONGC recruitment cell and they mentioned that submit NOC within one week otherwise your candidature will cancelled (and through tell phone also) and in return reply I have said sir in my undertaking I have already mentioned that In case of my final selection I will produce NOC. But they rejected my selection and declared result on 29.09.2015. I have filled RTI on [deleted] and in RTI reply I found that I got 74.37 marks and cutoff is 70.94.And I have also asked reason why I am not selected they have replied that “As per IOM no. DDN/Rectt/GT-2013/surface dated 29.09.2015 your name was not to be released since you have not submitted the NOC”. But question here raises that if I am not employed on last date of application why they asked me NOC(No objection Certificate) and for the same reason they have rejected my selection. And other case is that as I mentioned in undertaking I will produce NOC, In case of my final selection, why they not declared my result. Can I file case against ongc plz suggest me