Acrobat accessibility function errors: garbage notations and shifting positions

I encounter all kinds of problems using accessibility functions in adobe acrobat, maybe because the pdf is generated by latex. First, when I use automatically tag PDF, it adds lots of brackets on the formulas, as shown in the first picture. When I try to mannually label figures using the Fix reading order function, the position of the figure changed after I click figure, as shown in the difference between picture 2 and 3. What leads to these wired changes? How to solve that?