First of all make sure that you are done with amendments and recent case studies as provided in the RTP.
Then make try to go through with the Practice Manual and your summary notes.
In exam attempt every questions even if you don't know the exact answer but atleast you can write the relevant case laws and sections.
When you see the paper just manage your time to attempt those parts in which you can answer good and dedicate rest of the time in writing in which you less what atleast can write something relevant.
If you are getting 39 that means you are scoring less than that.
Write your paper with proper notes and briefings.
All the best...!!!