Can my job be denied if my caste certificate is in state govt format?

I had applied for a post in Indian coast guard. I'm of OBC caste and thus they asked me to show the certificate. But according to their rules, they needed OBC certificate of "central government format" but mine was of "Maharashtra state government format" so I was rejected before even commencing the selection process. Was my rejection fair? If no, what should I do now? If yes, is there any written law which says that if a candidate couldn't produce any particular document during an interview, can he get it later within some specific time period so I can go and claim my selection process back?