Central Board Of Secondary Education [CBSE] — My son board mark not satisfied

My son achieved 86 percentage in 10th CBSE board exam. Now in 12th board exam he scored only 72 percentage. My son's performance in 11th and 12th is good. My son scored in 92marks in maths and 88 in science in 10th board exam. But his 12th mark is very low as compared to other students marks. Most of the CBSE Students can't able entered the state government colleges (Tamil Nadu) with unfair marks. Mark scheme is not followed properly by board and respective school. Very unfair results.Hence my son's future is questioned❓. The board kindly be give the proper solution and I request that to make a revaluation of my son's 12th mark as soon as possible.

I believe that board will consider my request and give a reasonable solution.

My son's enrollment number 20656130
School code 55179( Laurel secondary school, Pattukkottai, Thanjavur district, Tamilnadu)

Thank you.