If you are using any of the below model of Keyboards and are facing an issue with detection of any particular key, please try the below steps to troubleshoot the issue.
Models:- Corona, Titan, Galactic, Black Eye, Neon, Aurora
Resolution 1:-Try removing the key cap carefully that isn't working and clean the area under and around it. Sometimes, its dust, hair or other debris fall into keyboard in course of time which interfere in movement with its circuitry. For Membrane keyboards like Galactic, Corona etc you will see a silicon tip on the keyboard under the keycap. Use a earbud and clean it and move it to the center of the key if it has shifted.
Resolution 2: For Resetting keyboard: Press Fn + Esc Key for 10 seconds simultaneously.
Resolution 3: For choosing keyboard lights: Fn + Scr Lk. This may be differ based on your keyboard model. Please refer to the keyboard manual for details.
Resolution 4: For changing light speed Fn + >, Fn+ <, Fn + up arrow and down arrow