After choosing and answer as the best answer, we have to refresh the page

Hello In my site here:
http://ask.pstuts.ir/
when someone clicks the green check mark near an answer, the page reloads but still the check mark is gray and you can click on it and again the same thing happens but if you refresh the page manually (with F5) you can see that it’s green!! I mean after clicking, the page reloads automatically but the changes aren’t visible but if you reload manually you can see the changes