@oussama-he make your router/routes.js a function that accepts a store parameter from your router/index.js. example:
// src/router/routes.js ... const routes = (store) => [ ... beforeEnter: (to, from, next) => { if (store.getters.isAuthenticated) { console.log('authenticated user'); next('timeline') } else next() } ... ] export default (store) => routes (store) // src/router/index.js import routes from './routes.js' export default function ({ store }) { // <-- accepts store as parameter const Router = new VueRouter({ scrollBehavior: () => ({ x: 0, y: 0 }), routes: routes(store), // <--- pass the store context to your routes.js ...