Since you did not provide an operating system, or browser here is the general uninstall re-install process
For Windows XP, Vista, and All variants of Windows 7 users and for the NPAPI or PPAPI version of Adobe Flash Player for Windows 8.X to 10 follow this guide below.
1) Download the Adobe Uninstaller here: https://helpx.adobe.com/flash-player/kb/uninstall-flash-player-windows.html#main_Download_ the_Adobe_Flash_Player_uninstaller
2) Grab the Offline install files that you need located here:
a) Firefox (NPAPI): https://fpdownload.macromedia.com/pub/flashplayer/latest/help/install_flash_player.exe
b) Opera (PPAPI): https://fpdownload.macromedia.com/pub/flashplayer/latest/help/install_flash_player_ppapi.e xe
c) Internet Explorer Active X (Win XP through 7): https://fpdownload.macromedia.com/pub/flashplayer/latest/help/install_flash_player_ax.exe
The main page for these links is at the bottom of this page under 'still having problems’: https://helpx.adobe.com/flash-player/kb/installation-problems-flash-player-windows.html#ma in-pars_header
Now that you have all the files you need you can begin, usually you do not have to uninstall, however it can be a good practice generally speaking as the Adobe Uninstaller takes care of certain thing that might be left over from older installs.
3) Make sure you have ALL Browsers closed, and the following applications closed as they use on version or the other of flash, this is not a complete list (check the system tray for the running application):
a) BattleNet browser
b) Yahoo messanger
c) Skype
d) Steam Browser
e) The Weather Channel App
4) Right Click on the Uninstaller and Run as Administrator to begin Uninstalling All variants of Adobe Flash Player; once again Windows 8.X and Windows 10 users the Integrated version WILL NOT be touched by this uninstaller. This should only take a few seconds.
5) Right click and run as administrator whichever variants you downloaded in step 2 one by one and install them.
That should be it and you should be able to play any flash content for the browser and plugin you installed for.
You can go to the following page to verify you have Flash Player Installed, and test it; you should see a little bouncing cube here: http://www.adobe.com/software/flash/about/
This page will just tell you the version: https://helpx.adobe.com/flash-player.html