What does it mean when it says " This function has too many statements (79) "? This is JavaScript by the way

What does it mean when it says that the function has too many statements? Is there a maximum code length I can have in functions? If you have any recommendations on how to shorten/fix my code, feel free to help me.

function keyDownHandler(e) {
  if (e.key == "KeyA") {
    letterDown = "a";
    console.log(keyDown);
    console.log(ballLetter);
  }else if (e.key == "KeyB") {
    letterDown = "b";
    console.log(keyDown);
    console.log(ballLetter);
  }else if (e.key == "KeyC") {
    letterDown = "c";
    console.log(keyDown);
    console.log(ballLetter);
  }else if (e.key == "KeyD") {
    letterDown = "d";
    console.log(keyDown);
    console.log(ballLetter);
  }else if (e.key == "KeyE") {
    letterDown = "e";
    console.log(keyDown);
    console.log(ballLetter);
  }else if (e.key == "KeyF") {
    letterDown = "f";
    console.log(keyDown);
    console.log(ballLetter);
  }else if (e.key == "KeyG") {
    letterDown = "g";
    console.log(keyDown);
    console.log(ballLetter);
  }else if (e.key == "KeyH") {
    letterDown = "h";
    console.log(keyDown);
    console.log(ballLetter);
  }else if (e.key == "KeyI") {
    letterDown = "i";
    console.log(keyDown);
    console.log(ballLetter);
  }else if (e.key == "KeyJ") {
    letterDown = "j";
    console.log(keyDown);
    console.log(ballLetter);
  }else if (e.key == "KeyK") {
    letterDown = "k";
    console.log(keyDown);
    console.log(ballLetter);
  }else if (e.key == "KeyL") {
    letterDown = "l";
    console.log(keyDown);
    console.log(ballLetter);
  }else if (e.key == "KeyM") {
    letterDown = "m";
    console.log(keyDown);
    console.log(ballLetter);
  }else if (e.key == "KeyN") {
    letterDown = "n";
    console.log(keyDown);
    console.log(ballLetter);
  }else if (e.key == "KeyO") {
    letterDown = "o";
    console.log(keyDown);
    console.log(ballLetter);
  }else if (e.key == "KeyP") {
    letterDown = "p";
    console.log(keyDown);
    console.log(ballLetter);
  }else if (e.key == "KeyQ") {
    letterDown = "q";
    console.log(keyDown);
    console.log(ballLetter);
  }else if (e.key == "KeyR") {
    letterDown = "r";
    console.log(keyDown);
    console.log(ballLetter);
  }else if (e.key == "KeyS") {
    letterDown = "s";
    console.log(keyDown);
    console.log(ballLetter);
  }else if (e.key == "KeyT") {
    letterDown = "t";
    console.log(keyDown);
    console.log(ballLetter);
  }else if (e.key == "KeyU") {
    letterDown = "u";
    console.log(keyDown);
    console.log(ballLetter);
  }else if (e.key == "KeyV") {
    letterDown = "v";
    console.log(keyDown);
    console.log(ballLetter);
  }else if (e.key == "KeyW") {
    letterDown = "w";
    console.log(keyDown);
    console.log(ballLetter);
  }else if (e.key == "KeyX") {
    letterDown = "x";
    console.log(keyDown);
    console.log(ballLetter);
  }else if (e.key == "KeyY") {
    letterDown = "y";
    console.log(keyDown);
    console.log(ballLetter);
  }else if (e.key == "KeyZ") {
    letterDown = "z";
    console.log(keyDown);
    console.log(ballLetter);
  }
}

I'm using JSFiddle, so maybe it's just an issue with the servers on the website. I can't think of any way to shorten the code, and if my keypress detection systems are wrong, please tell me so.