If connected to a PC, check the connections, reboot and try again. If this is a laptop or the first solution does not work, replace your keyboard, it sounds as if it's worn out. Laptop keyboards are connected with a 'ribbon' cable that can sometimes become dislodged. They are fiddly to re-connect and if you are not able or technically minded i do not suggest you DIY this repair, go to a professional.
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If connected to a PC, check the connections, reboot and try again. If this is a laptop or the first solution does not work, replace your keyboard, it sounds as if it's worn out.
Laptop keyboards are connected with a 'ribbon' cable that can sometimes become dislodged. They are fiddly to re-connect and if you are not able or technically minded i do not suggest you DIY this repair, go to a professional.