Did you have a liquid spill into the keyboard? Even still its hit or miss with a single key failing. You could try replacing the keycap & hinge unit to see if that helps, but beyond that it would require either replacing the discreet keyboard which is not for the faint of heart as you literally need to rip the old one out as you need to break it free from the plastic rivets which hold it in [https://www.amazon.com/Soonjet-Replacement-Keyboard-Keycaps-MacBook/dp/B0CX1VW5H3/ref=sr_1_9?|Replacement US Keyboard Keycaps Key Caps for MacBook Air 13 inch 2020 M1 A2337 A2179, Full Keycap with Removal Tool] Don't forget to get the needed screws! While cheaper its not an easy job I don't even do it any more as its too hard for my arthritic hands. I only replace the full uppercase unit [product|IF188-146] so while its pricy it ends up being the better repair as the pulling of the keyboard out often warps the case and makes remounting of the new keyboard a bit spongy if you forget the 80 or so screws to replace the rivets.