Many keys not working

Many keys of my keyboard are not working. This previously happened with the main enter key, but now both the enter keys, l, b, f, 3, 9, and many other keys are not working. Pressing t triggers endless forward slashes. My previous problem with the enter key was solved a few days later automatically, somehow, and I suppose this problem will too disappear a few days later, but I want to know the root cause of this problem, as it is happening frequently. Link

I am running Win10 on Dell laptop.