If you're using Internet Explorer, the problem is in your browser. The page(s) can't recognize the browser so they don't recognize the plugin's either. Microsoft has been aware of the problem since October 18, shortly after they released IE11.
So far, they've made NO indication that they have any plan to fix it soon.
Microsoft's recommendation is to use Compatibility View for affected pages, and "pretend" you're using an different browser. Trouble with that is it has seen limited success at best, and you have to individually enable it for EVERY page that has problems.
I'm not big on "pretending" so I recommend actually using another browser.
ANY of those will work where IE11 won't, with the Flash Player Plug-in (For all other browsers), and Chrome doesn't even need that because it has its own Flash Player plugin built in.