Hi Prakash!
Sorry that you're having trouble!
Definitely keep up the notes. They're a huge help, and a vital part of your prep. However, if you feel like their holding you back, it's worth taking a look at how much you are writing down. Many students end up taking notes almost as long as the prompts themselves, and this isn't helpful! When I'm making my notes, I use arrows, abbreviations, and sentence fragments to save time and space. No one will see them but me!
Aside from that, however, I'm not sure what to advise you. In particular, an 80% hit rate from the OG seems pretty good, all things considered. How are your verbal sectional scores turning out?
Also, have you noticed any partiuclar Q types giving you trouble? It's worth breaking down your errors. It's possible that CR is just generally tough for you, but you might discover that most of your errors are one particular type of question--and that discovery could lead to an easy solution.
I hope this helps!