Vue.js App not compiling after adding Vuex - vue.js

Question

I have been working on a web app and decided I needed to implement Vuex to help. I tried implementing it and messed up at first, but I don’t know what’s causing it now. I may be overlooking something but I just can’t find it, any help?
Router (index.js)
import Vue from 'vue'
import VueRouter from 'vue-router'
import Home from '../views/Home.vue'
import Products from '../views/Products.vue'
import ProductListView from '../components/ProductListView.vue'
Vue.use(VueRouter)
const routes = [
{
path: '/',
name: 'Home',
component: Home
},
{
path:'/products',
name: 'Products',
component: Products,
children: [
{
path: ':ptype',
name: 'ProductListView',
component: ProductListView,
props: true
}
]
},
{
path: '/about',
name: 'About',
// route level code-splitting
// this generates a separate chunk (about.[hash].js) for this route
// which is lazy-loaded when the route is visited.
component: () => import(/* webpackChunkName: "about" */ '../views/About.vue')
}
]
const router = new VueRouter({
mode: 'history',
base: process.env.BASE_URL,
routes
})
export default router
Store (store.js)
import Vue from 'vue'
import Vuex from 'vuex'
Vue.use(Vuex)
const store = new Vuex.Store({
state: {
count: 1
},
mutations: {
}
})
export default store
App (main.js)
import Vue from 'vue'
import App from './App.vue'
import router from './router'
import store from 'store.js'
Vue.config.productionTip = false
new Vue({
router,
store,
render: h => h(App)
}).$mount('#app')
I'm getting this error when I try running yarn serve in PowerShell
yarn run v1.22.4
$ vue-cli-service serve
'vue-cli-service' is not recognized as an internal or external command,
operable program or batch file.
error Command failed with exit code 1.