Failed to router for MPA with history mode

[cn-ryh]

I am developing a multi-page application that uses vue-router4 history mode for routing. When I use npm run serve, the access is normal. However, when I use live- server or http- server to access the builded dist folder, for pages that do not have secondary routing (for example, access to localhost:8081/login can be accessed normally), but for those pages with secondary routing (such as localhost:8081/user/1), It shows CANNOT FOUND /user/1 occurs.
Obviously this is because there is no access to the routing program at all.
It is worth mentioning that when I use hash (for example, localhost:8081/user/#/1), multi-level routing can be accessed normally.

Here is my code of router in user dictory.

import * as VueRouter from 'vue-router';
import training from './user-detail.vue';

const routes = [
    { path: '/:id', component: training },
];

const router = VueRouter.createRouter({
    history: VueRouter.createWebHistory(`user`),
    routes,
});

export { router };

[posva]

You need to configure the server to still return the index.html page: https://router.vuejs.org/guide/essentials/history-mode.html#Example-Server-Configurations