String Comparison Javascript

I was getting started on javascript and I faced difficulties comparing two strings successfully in React (or just Javascript in this case). Say I have the following function:

function compare(a, b) {
  var n = -1, m = 0;
  console.log(a, b, b === "important");    // prints here

  if (a === "important") {n = 2;}
  else if (a === "normal") {n = 1;}
  else {n = 0;}

  if (b === "important") {m = 2;}
  else if (b === "normal") {m = 1;}
  else {m = 0;}

  return n - m;
}

but the code’s output (after two separate executions) was

["normal"]
["important"]    // this case? b is "important"
false
["unimportant"]
["normal"]
false

I can’t see why the code above doesn’t work. Can anyone please explain? Thanks in advance.

EDIT

Function called in

sorter: (a, b) => compare(a.levels, b.levels),

Where a and b are

  {
    key: "1",
    title: "Eat",
    date: "2020-07-20 07:57",
    levels: ["important"]
  },
  {
    key: "2",
    title: "Sleep",
    date: "2020-07-20 07:57",
    levels: ["normal"]
  },

Note that the function is called in React. CodeSandbox Demo

function compare (a, b){
  function swit(v){
      switch (v){
        case 'important' :
          return 2;
        case 'normal' :
          return 1
          default :
            return 0
      }
  }
  return swit(a) - swit(b);
}
var normal = ["normal"];
var important = ["important"]
console.log(compare(normal[0] , important[0]))
console.log(compare(important[0] , important[0]))
console.log(compare(important[0] , normal[0]))