Why does mounted() fire more than once in Vue.js?

Question

Vue.js

Either I'm doing something wrong, or I don't understand something... but my mounted() code works three times. I added receiving data via api to it and now three requests are sent simultaneously.

<template>
    <div id="app" class="container">
        <AddCampaign/>
    </div>
</template>

import AddCampaign from './components/AddCampaign';

export default {
  name: 'App',
  components: {
            AddCampaign
        },
    data() {
        return {}
    }
}

Answer 1

Mounted in the AddCampaign component? We need all the code.