How to reset the setInterval() in Js?

Question

I need the ('http://localhost:3000/users') to be updated in realtime when the server is running. I have a function fetchSlots() running in a given setInterval. If any user added or deleted in the DB (i.e in the ('http://localhost:3000/users')).I need to fetch the newly added item and use it in the fetchSlots().Like if I run the server for the below code,it is fetching details every 30000ms.If I add a user to the db ,in the next interval,Newly added user details is not fetched .similary,if I remove a user from the db while the server is running,in the next interval that deleted user details also being fetched.Should I have to reset the interval after every 30000ms or how can I solve this issue.

Any help!

async function polling() {
    await axios.get('http://localhost:3000/users').then(async response => {
      for (let l = 0; l < response.data.length; l++) {
        slotFound = false;
        const apiCall = setInterval(async () => {
          await fetchSlots(response.data[l].pincode, response.data[l].emailid);
        }, 30000);
      }
    });
  }

Answer 1

to answer your title question : "How to reset the setInterval() in Js?" you can stop the interval by calling clearInterval with what setInterval returned.

clearInterval(apiCall);

but to do what you state in your description i feel like this would be much more straightforward.

async function polling() {
    const response = await axios.get('http://localhost:3000/users');
    for (let data of response.data) {
        slotFound = false;
        await fetchSlots(data.pincode, data.emailid);
    }
}
setInterval(polling, 30000);