now i dont trust the teacher in charge of my center so i would like to know the step by step process to recheck the exam and the retrieval of a copy from the original paper
Depends on the school. You contact your exams officer or exams department in your college request for the papers to be remark. If that does not work you can do some research on the website of the exam board of the exam which you took.
now i dont trust the teacher in charge of my center so i would like to know the step by step process to recheck the exam and the retrieval of a copy from the original paper