I still remember that when I was in school I was able to remember everything, but I degree college it is not possible, I am wondering why?
Dear student,
I hope you are doing well.
About your question, first I want to tell you the pattern and syllabus you studied as a child in school is not the same at advanced degree programs. In school most of the students by heart studies basically copy paste. This method is not helpful in higher studies as you have competitive questions.
Another problem is as you are growing and getting exposed to various new environments, students loose alot of focus on their studies. And it is very natural, it's nothing to be scared of.
Try not to by heart your studies now, understand the concept and reproduce your answers. From your 11th class students are not expected to copy paste answers as it is. That's the reason why we are offered answers in the form of points. It's done so that students can reproduce their own answers based on their understanding. Copy paste answers from the textbooks is not wrong but it just doesn't seem right at higher levels.
I hope you understand what I wish to explain.
Try to change your mode of studying as long as you score it will be ok.
All the best. Hope this helps