Actually I will clarify that, trying to get to the reason behind the non-reporting which might shed some light. The most obvious first place to look - in my view - is in the detail. Misunderstanding might have been a better word to use than error.
For example, say what you are reporting is not, in the police's view rather than yours, classified as a recordable crime, there would be a simple answer as to why they haven't been recorded. Hence my questions.
As you are trying to work out why crimes you have reported haven't been recorded rather than asking solely about policy from a more academic point of view, this to me is a sensible starting point rather than just looking at bare policy and may get to the root of your problem quicker.