The lack of self-knowledge may just be self-ignorance, but it can also be self-misunderstanding. If, for example, you are a stingy person but are not aware that you are --- you don't know that you are stingy, nor do you believe that you are not stingy, then you are just self-ignorant. But if you have the false belief that you are a generous person, then you have self-misunderstanding. This is an important distinction because which form your lack of self-knowledge takes makes some difference to how difficult it will be for you to gain the relevant self-knowledge.
It may appear that self-misunderstanding is a greater hurdle for self-knowledge, for you have to get rid of the false belief as well as acquiring the true one. The false belief stands in the way, and it seems to take more effort to acquire the true belief than in the case of mere self-ignorance.
There is, however, reason to think that self-misunderstanding is, at least in some cases, less of a hurdle for self-knowledge. If you have a false belief about yourself (such as the belief that are a generous person, when in fact you are stingy), it may sooner or later come into conflict with what happens around you (such as your repeatedly refusing to help your friends even when you can easily help them). The conflict, or rather your experience of it, can prompt you to consider the possibility that your belief is false and to see what happens around you as evidence for the opposite belief, that is, the true one.
By contrast, if you are merely self-ignorant, then even if what happens around you is evidence for a certain belief about yourself, you may not even pay attention to it. When this is the case, it is not that you dismiss the evidence; you simply don't see the import of what happens around you --- you don't see it as evidence for or against anything.