When once again you turn on your laptop and suddenly the keyboard stops Working, it looks like a severe problem. After all, unlike desktop computers, all components are connected, they are not so easy to turn off or change. First of all, you need to decide: the whole input panel or individual keys do not work. Therefore, Before we get rid of the failed component, we should find out: why does the keyboard on the laptop not work? There are several answers to this question, and there are many solutions to this problem. Let's find out about them to try to deal with the problem yourself and fix it.

WHAT TO DO IF THE KEYBOARD DOES NOT WORK ON A LAPTOP - WE FIND THE CAUSE AND FIX IT OURSELVES·        
External problems May be Responsible for Laptop Keyboard Is Not WorkingWhy Do we immediately pay attention to obvious problems? Because one of the most common reasons for a broken keyboard on a laptop is dirt, dust or liquid, and also issues with the cable, which will be discussed a little later. Naturally, if you poured a cup of coffee on the keys, you will immediately guess why the device stopped working.If Liquid gets in, take immediate action: disconnect the device from the power supply, disconnect the battery and turn the laptop over so that the fluid has drained out. Then try to disassemble the device, put it in a dry place to dry. By the way, this process takes quite a lot of time, so you have to wait a week or even two until all the components return to normal. Only then will you know if your laptop is still working or not.

Source:
https://trilliontechng.com/what-to-do-if-the-laptop-keyboard-is-not-working-fix-it-ourselves/