I ave to solve som issue about one of my javascript classes, it may concern an issue concerning about internal variables scoping…?

I just created a counter class that seems to work almost okay.
Unfortunately there is an issue that I cannot identify.
I instance my class twice with a different name but the parameters remain the same in terms of the chrono max limit.
Thanks to anyone who could help me…

I’m trying to create a class that can display a counter but there is a problem with the parameters. Of course I could just create a simple function instead but that’s not what I’m trying to do. I would like to stay in the same perspective if possible… Thanks to anyone who could help me…

I’ll let you look at the code a little further down.

document.addEventListener("DOMContentLoaded", (event) => {
  console.log("DOM fully loaded and parsed");
});

class SuperCounter {
  constructor(cumul, limit) {
    this.cumul = cumul;
    this.limit = limit;
  }
  add() {
    if (this.cumul === this.limit) {
      console.warn('Counter just reached to the limit');
      clearInterval(ignition)
    };
    return {
      result: this.cumul++,
      //limit: this.limit,
    }
  }
}

const firstCounter = new SuperCounter(1, 50);
const secondCounter = new SuperCounter(1, 150);

const ignition = setInterval(displayCounter, 100);

function displayCounter() {
  document.querySelector("#chrono1").innerHTML = /*html*/ `<h2>Chrono #1 : ${firstCounter.add().result}</h2>`
  document.querySelector("#chrono2").innerHTML = /*html*/ `<h2>Chrono #2 : ${secondCounter.add().result}</h2>`
};
<h3 id="chrono1"></h3>
<h3 id="chrono2"></h3>