Central Board Of Secondary Education [CBSE] — Reduction of marks due to previous students performance

I'm SASMITA V of class XII, CBSE Board student, Chellammal Vidyalaya Senior Secondary School (Affiliation code 1930673), Kallanai Road, Tiruchirapalli, Tamilnadu. I got less Mark in biology and physics in class XII board results released on 30th July 2021 . I got 95% (100%in mathematics) in class X CBSE Board exam and also I got good score in class 11th and 12th exams conducted in school . While I contact the school officials they told that it few marks was changed by CBSE and its not the school who sent . This is very disappointing and it affects my future .My past two years hardwork has become useless, because of the previous one year students performance( we are the 2nd batch of the school). Don't judge the student performance from one year passed out students. Why should I won't study better than previous year students?..why is my future affected because of them?.So, I NEED JUSTICE

NAME OF THE STUDENT: SASMITA V
SCHOOL CODE:55597
ROLL NO:20651955