That is my scoring which I considered:
2 years education + 2 years Bachelor + 1 year diploma (My assumed score was 22) but they awarded me 20 points.
Wife having same Bachelor education as mine but they awarded only 3 points instead of 4 points.
I was already on borderline having 67 points according to my calculation but they have not awarded so.
Sorry to hear that. It is always a risky thing to apply having met 67 points according to our calculations!
Anyways. Don't lose hope. Education thing you cannot change, so forget about it now.
How about IELTS? What was your score and how many points you got there? Any chance you can increase your band to get higher points?