If I were you, I'd do past papers, so I know what I need to work on and what needs more attention.
I admit I have been slacking a bit with studying business studies but I was going to recommend this (or something similar). However this is because Business for me is pretty much the same as it seems for you, where lots of it is common sense and things I can review are the more heavy stuff that I can do closer to the exam.
Basically OP I would recommend actually doing questions. Like in past papers. If you're not remembering your notes then it's probably pointless reading them. Also I recommend against memorising the notes as they will not be the main thing tested. ie. they are not your end goal. The exam is going to see how well you can USE the information in the notes rather than just RECALLING your notes. So I think that memorising them is a waste of time, especially if you're not even remembering them.
Basically I think that what's happening is you're reading your notes but because of the level of abstraction you don't connect links to them and so can't actually remember them the next day. In other words, you're reading them but they seem disconnected to you since you don't see practical uses of them and you can't see how their useful for you to answer questions in an exam. So the information gets read but doesn't have any practical/useful relevance and you don't retain or absorb anything so it just gets forgotten. Furthermore you can't disentangle the useful information and what you "need" and the DEPTH needed so it all becomes a mass of words in the end. So you may as well be reading a technical paper on astrophysics! That's my guess of what you're going through. And don't worry, I can see why/how you'd be forgetting things this way, especially for a subject like Business Studies. There's a lot of dry content that may seem abstract/far away and irrelevant.
To thus, actually make good use of study time I'd recommend do questions, especially from past HSC papers. This will actually test your knowledge and when you get it wrong you will be able to focus on these areas better. This will actually provide some way for you to remember content easier as you will be able to link the information to questions that can be asked. It also helps consolidate what you do know and increase your knowledge on the subject. It will also help you understand what is in the paper and perhaps help you develop exam techniques. There are many benefits to past paper questions.
All that being said, I'm not at all against notes or memorising things or whatever. I'm not saying that they are completely useless and that you should get rid of them. I have notes myself and I'm sure you've learnt/consilidated information by just writing them! Instead, use them as a TOOL rather than as your GOAL. ie. Don't make it your GOAL to memorise them, but use them in whatever learning aid works best to achieve the best knowledge of the course (which can be discovered through past papers). Because at the end of the day, the examiner isn't going to be concerned about whether or not you memorised your notes, but rather your knowledge of the course. So use them in whatever way helps you. If you need them for practicing past papers use them. If it helps you to memorise a particular section for whatever reason, use them. I'm not against notes, as long as their used effectively to learn and understand.
Also everyone is different. If you're doing notes because you've been told they are the "correct study method" but they are not helping then you shouldn't just use them. Some notes may be really helpful for others, either compiling tens of pages of them and for others (like me) they may not be that useful at all. I've probably got a few pages of notes that I just compiled very quickly for exam cram before the trials, for the purpose of compiling what I needed to know and memorising the key facts I still needed. So do whatever works best for YOU and what will help you the most.
Tldr;
1. I recommend not using notes just to memorise them for the sake of it.
2. Do past questions to make better connections between information and questions that can pop up in the exam.
3. I'm not against notes and use them by all means in whatever way is helpful but try use them effectively.
Sorry for the really long post (I do this a lot!), feel free to skip and read the Tldr if you want. But I hope something there helped
