Issue with Indian passport acquiring

Background -- My name Mukesh Thapa I am born (30th Mar 1988) and brought up in Delhi. All my schooling and graduation is done from Delhi. My parents belong from Nepal. My father moved to Delhi in 1968 (not documented) and my mother in 1984 (not documented). My father worked as a Lift operator in a company for serval years and retired in 2014. My parents has Adhar card, Voter ID, pan card (father) but does not have any Passport(Indian/Nepal). Issue -- I am working in MNC company and currently in Mumbai for last 8-9 years. Few years back I got opportunity to fly onshore so I applied for tatkal Passport. I received my passport in 3 days but later got a SMS that police had submitted adverse report and your passport has been revoked. I went to passport office for more clarification and reason they said "As per Indian constitution by birth you are not an Indian as you are born after 1986 and one of your parent should have an Indian passport at your time of birth". So what can I do here ??