问发出请求时出错，如何解决无法加载资源: net::ERR_CONNECTION_REFUSED ...127.0.0.1:12709/staffregister问题？

import type { AxiosInstance, AxiosRequestConfig } from 'axios'
import axios from 'axios'
import router from "@/router";
import { ElMessage } from 'element-plus'

const instance: AxiosInstance = axios.create({
  // baseURL: import.meta.env.VITE_API_URL,
  baseURL:'http://127.0.0.1:12709',
  timeout: 10000,
  headers: {
    'Content-Type': 'application/json',
  },
})
//添加响应拦截器
instance.interceptors.response.use(
  result=>{
  console.log(result.data);
      return result.data;
  },
  err=>{
      alert('服务异常');
      return Promise.reject(err);//异步的状态转化成失败的状态
  }
)

// 添加请求拦截器，打印请求信息便于调试
instance.interceptors.request.use(
  (config) => {
    console.log('Request:', {
      method: config.method?.toUpperCase(),
      url: config.url,
      data: config.data,
    })
    return config
  },
  (error) => {
    return Promise.reject(error)
  },
)

instance.interceptors.response.use(
  result=>{
  console.log(result.data);
      return result.data;
  },
  err=>{
      alert('服务异常');
      return Promise.reject(err);//异步的状态转化成失败的状态
  }
)

// // 响应拦截器
instance.interceptors.response.use(
  (response) => {
    const res = response.data
    if (!res.success) {
      return Promise.reject(new Error(res.message || '请求失败'))
    }
    return res
  },
  (error) => {
    const errorMsg = error.response?.data?.message || error.message || '网络错误'
    ElMessage.error(errorMsg)
    return Promise.reject(error)
  },
)

export default {
  get: (url: string, config?: AxiosRequestConfig) => {
    return instance.get(url, config)
  },
  post: (url: string, data?: unknown, config?: AxiosRequestConfig) => {
    return instance.post(url, data, config)
  },
  put: (url: string, data?: unknown, config?: AxiosRequestConfig) => {
    return instance.put(url, data, config)
  },
  delete: (url: string, config?: AxiosRequestConfig) => {
    return instance.delete(url, config)
  },
}

// export default instance;

  methods: {
    login(loginForm) {
      this.$refs['loginForm'].validate(async (valid) => {
        if (valid) {
          this.loadingbut = true
          this.loadingbuttext = '登录中...'
          try {
            const res = await stafflogin({
              uname: loginForm.uname,
              upwd: loginForm.upwd
            })
            if (res === 1) {
              this.loginSuccess(loginForm.uname)
            } else {
              this.$alert('用户名或密码错误！', { confirmButtonText: '确定' })
            }
          } catch (error) {
            this.$alert('登录失败，请稍后重试', { confirmButtonText: '确定' })
          } finally {
            this.loadingbut = false
            this.loadingbuttext = '登录'
          }
        } else {
          this.$alert('表单验证失败', { confirmButtonText: '确定' })
          return false
        }
      })
    },
    cancel() {
      this.$refs['loginForm'].resetFields()
    },
    showRegister() {
      this.registerVisible = true
      this.refreshCaptcha()
    },
    // 生成随机账号
    generateAccount() {
      const chars = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789'
      let result = ''
      for (let i = 0; i < 12; i++) {
        result += chars.charAt(Math.floor(Math.random() * chars.length))
      }
      return result
    },
    // 刷新验证码
    refreshCaptcha() {
      const chars = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789'
      let result = ''
      for (let i = 0; i < 4; i++) {
        result += chars.charAt(Math.floor(Math.random() * chars.length))
      }
      this.captchaCode = result
    },
    // 登录成功处理方法
    loginSuccess(username) {
      this.$alert('登录成功', {
        confirmButtonText: '确定',
        callback: () => {
          sessionStorage.setItem("uname", username)
          sessionStorage.setItem("password", this.loginForm.upwd)
          localStorage.setItem("token", "logged_in")
          let path = this.$route.query.redirect
          this.$router.replace({ path: path === '/' || path === undefined ? '/home/homeshou' : path })
        }
      })
    },
    // 修改注册方法
    register() {
      this.$refs.registerForm.validate(async (valid) => {
        if (valid) {
          if (this.registerForm.captcha.toLowerCase() !== this.captchaCode.toLowerCase()) {
            this.$alert('验证码错误', { confirmButtonText: '确定' })
            return
          }
          this.registerLoading = true

          try {
            const res = await staffregister({
              ID: this.registerForm.idCard,
              password: this.registerForm.password
            })
            console.log(res, '1111')
            if (res == 0) {
              this.$alert('注册失败，请稍后重试', { confirmButtonText: '确定' })
              return
            }

            this.$alert(`注册成功！您的员工号是：${res}，请妥善保管。`, {
              confirmButtonText: '确定',
              callback: () => {
                this.registerVisible = false
                this.registerForm = {
                  password: '',
                  confirmPassword: '',
                  idCard: '',
                  captcha: ''
                }
              }
            })
          } catch (error) {
            this.$alert('注册失败，请稍后重试', { confirmButtonText: '确定' })
          } finally {
            this.registerLoading = false
          }
        }
      })
    }
  }
}