How do you skip over an array of JSON objects when randomly pulling data with fetch?

I'm creating an app that randomly pulls one of 40 objects from a JSON array in a JSON file (people.json) when a button is clicked. It works but will often pull duplicates. How would I go about skipping an object in the JSON file if that object has already been randomly called so that I can avoid duplicates?

Here is the data I have so far:

// Fetch random user and add money
async function getRandomUser() {
  const res = await fetch('people.json');
  const data = await res.json();

  let randomUser = data[Math.floor(Math.random() * data.length)];

  addData(randomUser);
}

// Add new obj to data array
function addData(obj) {
  data.push(obj);

  updateDOM();
}