axios数据，报错Cannot read properties of undefined (reading 'protocol')

引入了axios，然后拿到res想看一下数据拿到没，结果报错

import axios from 'axios'

axios({
    URL: 'http://123.207.32.32:8000/home/multidata',
}).then(res => {
    console.log(res);
})

main.js怎么写的
import axios from "axios";
Vue.prototype.axios = axios