Central Board Of Secondary Education [CBSE] — Wrong marks in 12th, need to take actions on college and update accurate result

This is a very grave issue and lot of students including my brother are facing problems of wrong marks given in 12th CBSE board exam 2021. This is going to affect his whole future because of a ignorance/mistakes done by colleges.
As an IIT aspirant, my brother studied hard and got 95% in 10th, 92% in 11th as a result of it. But after seeing result of 12th, we were shocked to know the college gave him only 76%. He is looking for IIT JEE and BITS exam for which PCM Mark's criteria is 75% and he just got 74% in PCM, hence is now not even eligible for the exam.

His details:
CBSE Roll No is 11689395
School Code - 10480
School Name - Aklank Public school, Kota, Rajasthan

Appearing for re-exam is not at all possible interrupting JEE and other exams preparations. On top of it we have shifted from Kota to Mumbai and took all exam centers from here. So again appearing for board exam from Rajasthan in the entrance exam schedule is not at all possible.

This is going to ruin all his aspirations.
This is definitely a wrong score and needs to be re-evaluated and corrected immediately, and strict action needs to be taken on this ignorance/mistake as well.