MacBook Air: One key doesn't work – replace it?

Hi, I have a 2015 MacBook Air, and it's still working perfectly. There's just one annoying problem: The letter P on the keyboard doesn't work. I can press it as often as I want, with as much or as little pressure as I want, but nothing happens. I have no choice but to copy and paste the letter, which is pretty annoying.

It only affects the P key, and I can't find any obvious fault. The key doesn't stick, jam, or catch. It feels completely normal.

What can I do? Do I need to replace the entire keyboard because of one letter?

Thank you.