Before you fail the subject:
1.consider applying for special provisions / accessability / special circumstances
2.apply to get the subject mark remvoed from your transcript due to special circumstances
3. before you fail, contact the subject coodinator saying something like hey: due to these circumstances I haven't done well in the course, however, I believe that I can achieve all student learning objectives to standard expected. However, due to these prior failures, this won't be adequately reflected in my course mark. If I obtain a high mark in the final exam reflecting my academic achievement in the course and preparedness for future coursework, would it be possible to reweight my previous course marks towards the final exam slightly such that I can obtain a passing mark. You can also offer to do redos on assignments/additional essays etc to a credit/distinction average to get a slight increase on your original work such that you pass the course. It's better to suggest solutions yourself on how to prove you achieved course objectives as your teacher's focus is on their research, not on students - helping you is just adding extra work for them. You need to ease their burden.
This is always worth it, even if it only succeeds with 10% chance
4. consider hiring a tutor, BTW look up UTSSA tutoring service. it is cheap and for uts subjeccts.