When I enter text inside an input that as v-model all the steps of my stepper shows.

How can I work with v-model inputs inside a stepper ?

My code is :

<template>
  <section class="container">
    <mdb-stepper
      :submit-function="onSubmit"
      buttons
      within
      next-btn="Suivant"
      prev-btn="Précédent"
      submit-btn="Enrégistrer">
      <mdb-step
        slot="content"
        name="Données de prévisualisation" 
        icon="eye">
        <h3 class="font-weight-bold pl-0 my-4"><strong>Données de prévisualisation</strong></h3>
        <mdb-input 
          v-model="editedFlat.previewTitle" 
          label="Titre" />
        <mdb-input 
          v-model="editedFlat.city" 
          label="Ville" />
        <mdb-input 
          v-model="editedFlat.previewContent" 
          label="Texte de prévisualisation" />
        <mdb-input 
          v-model="editedFlat.price" 
          label="Prix" />
        <mdb-file-input 
          btn-color="primary" />
        <img 
          v-if="flat !== null" 
          :src="flat.thumbnail" >
      </mdb-step>

      <mdb-step
        slot="content"
        name="Galerie de photos" 
        icon="photo">
        <h3 class="font-weight-bold pl-0 my-4"><strong>Galerie de photos</strong></h3>
        <mdb-file-input 
          multiple 
          btn-color="primary"/>
        <mdb-container 
          v-if="editedFlat.photos.length > 0" 
          class="mt-5">
          <mdb-row class="mdb-lightbox">
            <mdb-col 
              v-for="(photo, index) in editedFlat.photos"
              :key="index"
              md="4" 
              @click="onConfirm(index)">
              <figure>
                <img 
                  :src="photo"
                  class="img-fluid" 
                  alt="">
              </figure>
            </mdb-col>
          </mdb-row>
        </mdb-container>
      </mdb-step>

      <mdb-step
        slot="content"
        name="Informations sur l'appartement" 
        icon="pencil">
        <h3 class="font-weight-bold pl-0 my-4"><strong>Informations sur l'appartement</strong></h3>
        <mdb-input 
          v-model="editedFlat.title" 
          label="Titre de l'anonnce" />
        <mdb-textarea
          v-model="editedFlat.content"
          :rows="15" 
          label="Contenu de l'annonce" />
        <mdb-input 
          v-model="editedFlat.numRef" 
          label="Numéro de référence" />
        <mdb-input 
          v-model="editedFlat.locality" 
          label="Localité" />
        <mdb-input 
          v-model="editedFlat.nbRooms" 
          label="Nombre de pièces" />
        <mdb-input 
          v-model="editedFlat.floor" 
          label="Étage" />
        <mdb-input 
          v-model="editedFlat.nbBathrooms" 
          label="Nombre de salle de bains" />
        <mdb-input 
          v-model="editedFlat.nbShowers" 
          label="Nombre de douches" />
        <mdb-input 
          v-model="editedFlat.surface" 
          label="Surface habitable" />
        <mdb-input 
          v-model="editedFlat.yearConstructed" 
          label="Année de construction" />
      </mdb-step>

      <mdb-step
        slot="content"
        name="Finalisation" 
        icon="check">
        <h3 class="font-weight-bold pl-0 my-4"><strong>Finalisation</strong></h3>
        <h2 class="text-center font-weight-bold my-4">Vous avez terminer!</h2>
      </mdb-step>
    </mdb-stepper>

    <mdb-modal
      v-if="showModal9"
      frame
      position="top"
      @close="showModal9 = false">
      <mdb-modal-body class="text-center">
        <span>Êtes-vous sûr de vouloir supprimer cette photo ?</span>
        <mdb-btn
          color="secondary"
          @click.native="showModal9 = false">Annuler</mdb-btn>
        <mdb-btn 
          color="primary" 
          @click="onDelete">Supprimer</mdb-btn>
      </mdb-modal-body>
    </mdb-modal>
  </section>
</template>

<script>
import {
  mdbModal,
  mdbModalBody,
  mdbBtn,
  mdbStepper,
  mdbStep,
  mdbInput,
  mdbFileInput,
  mdbTextarea
} from 'mdbvue'

export default {
  name: 'AdminFlatForm',
  components: {
    mdbModal,
    mdbModalBody,
    mdbBtn,
    mdbStepper,
    mdbStep,
    mdbInput,
    mdbFileInput,
    mdbTextarea
  },
  props: {
    flat: {
      type: Object,
      required: false,
      default: null
    }
  },
  data() {
    return {
      showModal9: false,
      deletedPhotoIndex: null,
      editedFlat: this.flat
        ? { ...this.flat }
        : {
            previewTitle: '',
            city: '',
            thumbnail: '',
            previewContent: '',
            price: '',
            photos: [],
            title: '',
            content: '',
            numRef: '',
            locality: '',
            nbRooms: '',
            floor: '',
            nbBathrooms: '',
            nbShowers: '',
            surface: '',
            yearConstructed: ''
          }
    }
  },
  methods: {
    onSubmit() {
      this.$emit('submit', this.editedFlat)
      this.$router.push('/admin')
    },
    onConfirm(index) {
      this.deletedPhotoIndex = index
      this.showModal9 = true
    },
    onDelete() {
      this.editedFlat.photos.slice(this.deletedPhotoIndex, 1)
    }
  }
}
</script>