as you mention your jee main score is 70 percentile but you are obc but not mention.

so you will treated as general category . as there is no any process in jee main to change your name or category if you donot mention when form is you applied.

at 291774 rank you will not able to qualify the jee main as you are in general category

so i suggest to give next attempt with more effort so that you will get good marks