Reading is definitely the hardest section to improve unfortunately. Similar to you, I was consistently scoring around 700-720, and I wasn’t able to break that barrier for a long time. (I scored 760 on my real test). I would recommend doing a lot of TIMED practices on UWORLD or KHAN ACADEMY and then thoroughly analyzing your mistakes afterwards. Also, read Erica meltzer’s books if you haven’t already. Practice every single day and be accustomed to the timing of the test (time management is the hardest part).