It’s hard to say what exactly you are doing wrong because I’m not sure how you have been preparing and studying, but perhaps switching it up would help. For instance, if you are using a certain app to study, maybe a different app, book, or other method would be better. I highly recommend taking a board review class, if you haven’t already. They tend to give you an abbreviated study guide which can help you focus your studying. Also, practice tests, if only to practice with the way questions are asked, I found to be very helpful.
When it comes to taking the exam, what I did was read the question and (quickly) think of what my answer would be before even looking at the answer choices. If what first came to my head was in the list of answers, I chose that for my answer and didn’t second guess myself. Critical thinking is a must, but overthinking and second guessing yourself is not overly helpful.
I wish you the best of luck – third time’s a charm! You got this!