I want to give nios with 5 subjects as required by jee main 2015. what should i do?

I passed my 12th 2012-2013,but failed in math which included physical education.due to low %tage i gave improvement exam 2013-2014 for five subjects again failed in maths. now, i want to give nios board exam but they are saying that you can only appear for 4 subjects as you are already passed.