ES6 Prevent Object Not Working

[TypeError: Cannot assign to read only property ‘PI’ of object ‘#’]

  **Your code so far**

function freezeObj() {
const MATH_CONSTANTS = {
  PI: 3.14
};
// Only change code below this line
Object.freeze(MATH_CONSTANTS);

// Only change code above this line
try {
  MATH_CONSTANTS.PI = 99;
} catch(ex) {
  console.log(ex);
}
return MATH_CONSTANTS.PI;
}
const PI = freezeObj();
  **Your browser information:**

User Agent is: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/96.0.4664.110 Safari/537.36

Challenge: Prevent Object Mutation

Link to the challenge: