Validação cadastro em Vue js

Boa tarde pessoal, qual é o erro no campo CPF?

<template>
 <v-container fluid fill-height>
 <v-layout align-center justify-center row fill-height wrap>
 <v-flex xs10 sm7 md5 lg3 xl2>
 <v-form
 data-vv-scope="form1"
 :model="form1"
 lazy-validation
 @submit.prevent="submitForm('form1')"
 autocomplete="off"
 method="post"
 >
 <v-card class="elevation-18 my-4">
 <v-toolbar flat color="transparent">
 <v-toolbar-title>{{ $t('register_head') }}</v-toolbar-title>
 </v-toolbar>
 <v-card-text>
 <v-alert
 :value="form1.has_error && !form1.success"
 type="error"
 class="mb-4"
 >
 <span v-if="form1.error == 'registration_validation_error'">{{ $t('server_error') }}</span>
 <span v-else-if="form1.error == 'limitation_reached'">{{ $t('campaign_customer_sign_up_limit') }}</span>
 <span v-else>{{ $t('correct_errors') }}</span>
 </v-alert>
 <v-text-field
 v-model="form1.name"
 data-vv-name="name"
 v-validate="'required|min:2|max:32'"
 :label="$t('enter_your_name')"
 :data-vv-as="$t('name')"
 :error-messages="errors.collect('form1.name')"
 required
 prepend-inner-icon="person"
 ></v-text-field>
 <v-text-field
 type="email"
 v-model="form1.email"
 data-vv-name="email"
 v-validate="'required|max:64|email'"
 :label="$t('enter_email')"
 :data-vv-as="$t('email_address')"
 :error-messages="errors.collect('form1.email')"
 required
 prepend-inner-icon="email"
 ></v-text-field>
 <v-text-field
 type="number"
 v-model="form1.cpf"
 data-vv-name="cpf"
 v-validate="'required|min:11|max:11'"
 :label="$t('digite_cpf')"
 :data-vv-as="$t('cpf_numero')"
 :error-messages="errors.collect('form1.cpf')"
 required
 prepend-inner-icon="person"
 ></v-text-field>
 <v-text-field
 v-model="form1.password"
 data-vv-name="password"
 v-validate="'required|min:8|max:24'"
 :label="$t('enter_password')"
 :data-vv-as="$t('password')"
 :error-messages="errors.collect('form1.password')"
 :type="show_password ? 'text' : 'password'"
 :append-icon="show_password ? 'visibility' : 'visibility_off'"
 @click:append="show_password = !show_password"
 required
 prepend-inner-icon="lock"
 ></v-text-field>
 <v-checkbox
 type="checkbox"
 v-model="form1.terms"
 data-vv-name="terms"
 v-validate="'required'"
 :label="$t('agree_to_terms')"
 :data-vv-as="$t('terms')"
 :error-messages="errors.collect('form1.terms')"
 value="1"
 required
 >
 <template v-slot:label>
 <div>
 {{ $t('i_agree_to') }}
 <v-tooltip bottom>
 <template v-slot:activator="{ on }">
 <a
 target="_blank"
 :href="$router.resolve({name: 'legal'}).href"
 @click.stop
 v-on="on"
 >
 {{ $t('terms_and_policy').toLowerCase() }}
 </a>
 </template>
 {{ $t('opens_in_new_window') }}
 </v-tooltip>
 </div>
 </template>
 </v-checkbox>
 </v-card-text>
 <v-card-actions>
 <v-btn color="primary" large block :loading="form1.loading" :disabled="form1.loading" type="submit" class="ml-0">{{ $t('create_account') }}</v-btn>
 </v-card-actions>
 </v-card>
 <v-btn @click="toLogin" :disabled="form1.loading" large block text class="no-caps"><v-icon size="16" class="mr-1">arrow_back</v-icon> {{ $t('back_to_login') }}</v-btn>
 </v-form>
 </v-flex>
 </v-layout>
 </v-container>
</template>
<script>
 export default {
 $_veeValidate: {
 validator: 'new'
 },
 data() {
 return {
 show_password: false,
 form1: {
 loading: false,
 terms: '',
 name: '',
 email: '',
 password: '',
 locale: '',
 timezone: '',
 has_error: false,
 error: '',
 errors: {},
 success: false
 }
 }
 },
 created () {
 this.form1.locale = Intl.DateTimeFormat().resolvedOptions().locale || null
 this.form1.timezone = Intl.DateTimeFormat().resolvedOptions().timeZone || null
 },
 computed: {
 campaign () {
 return this.$store.state.app.campaign
 }
 },
 methods: {
 toLogin() {
 this.$router.push({name: 'login'})
 },
 submitForm(formName) {
 this[formName].has_error = false
 this[formName].loading = true

 this.$validator.validateAll(formName).then((valid) => {
 if (valid) {
 this.register(formName);
 } else {
 this[formName].loading = false
 return false;
 }
 });
 },
 register(formName) {
 var app = this[formName]
 this.$auth.register({
 data: {
 language: this.$i18n.locale,
 uuid: this.$store.state.app.campaign.uuid,
 name: app.name,
 email: app.email,
 password: app.password,
 locale: app.locale,
 timezone: app.timezone,
 terms: app.terms
 },
 success: function () {
 app.success = true

 this.$auth.login({
 rememberMe: true,
 fetchUser: true,
 params: {
 locale: this.$i18n.locale,
 uuid: this.$store.state.app.campaign.uuid,
 email: app.email,
 password: app.password,
 remember: true
 },
 success () {
 // Handle redirection
 this.$router.push({name: 'points'})
 }
 })
 },
 error: function (res) {
 app.has_error = true
 app.error = res.response.data.error
 app.errors = res.response.data.errors || {}

 if (app.error == 'limitation_reached') {
 app.name = ''
 app.email = ''
 app.password = ''
 }

 for (let field in app.errors) {
 this.$validator.errors.add({
 field: formName + '.' + field,
 msg: app.errors[field][0]
 })
 }
 app.loading = false
 }
 })
 }
 },
 }
</script>