Hello friends I am tired of getting this error when i count a length of notification by using vue.js and Laravel it show error,Uncaught (in promise) TypeError: Cannot read property 'forEach' of undefined plz help me. here is my code.

store.js

import Vuex from 'vuex'
import Vue from 'vue'

Vue.use(Vuex)

export const store = new Vuex.Store({
state: {
    nots: []

},
getters: {
    all_nots(state) {
          return state.nots
    },
    all_nots_count(state) {
          return state.nots.length
    },

},
mutations: {
    add_not(state, not) {
          state.nots.push(not)
    },
}
})

UnreadNots.vue

<template>
  <li>
        <a href="/notifications">
              Unread notifications
              <span class="badge">{{ all_nots_count }}</span>
        </a>
  </li>
  </template>
 <script>
  export default {
        mounted() {
              this.get_unread()
        },
         methods: {
              get_unread() {
                    this.$http.get('/get_unread')
                        .then( (nots) => {
                              nots.body.forEach( (not) => {
                                    this.$store.commit('add_not', not)
                              })
                        })
              }
        },
        computed: {
              all_nots_count() {
               return this.$store.getters.all_nots_count
              }
        }

    }
</script>

web.php

Route::get('get_unread', function(){
    return Auth::user()->unreadNotification;
  });