The same problem has happened to me twice before. The first time it was easily fixed by pressing Ctrl+Shift+Num Lk. The second time the same combination did not work but my keyboard sort of fixed by itself after leaving it for a night. This time nothing is working and more keys are not working too. For example the Num Lk.
All 3 times occurred while playing tetris (idiotically I didn’t seem to learn my lesson), but the weird part is that I only use the arrow pad, the space bar, and c, and all those buttons seem to still work (besides the right arrow).