There could be several reasons why your keyboard is not working in Counter-Strike. Firstly, you should verify that you don't have any other controller connected to your PC as this could interfere with your keyboard. If this is not the issue, you should reinstall the keyboard driver.
If still it doesn't work then you should delete config.cfg and autoexec.cfg in SteamApps\common\Counter-Strike Global Offensive\csgo\cfg, then reassign the keys as it is possible for the files to modified.
If you still experience this problem you should refresh your Steam files as they can get damaged or corrupted. To do so, you need to follow the tutorial available at Steam support.
If that doesn't work please contact the Steam support to get specific help with your issue.
