axios发送到后端controller的数据一直是null

axios发送post请求到后端controller接受参数为null

// 登录Controller
@RequestMapping(value = "/login", method = RequestMethod.POST)
    @ResponseBody
    public String login(@Param("account") String account, @Param("password") String password) {

        System.out.println(account + " " + password);
        User byAccount = service.getUser(account, password);
        System.out.println(byAccount);
        if (byAccount != null) {
            System.out.println("登录成功");
            return "true";
        } else {
            System.out.println(account + " " + password);
            System.out.println("登录失败");
            return "false";
        }
    }

<body>
<div id="login" class="login">
    <form id="l" action="/login" method="post">
        <h1>登录测试h1>
        <input id="account" type="text">账号<br>
        <input id="password" type="password">密码<br>
        <input type="button" id="btn" value="提交">
    form>
div>
body>
<script src="https://unpkg.com/axios/dist/axios.min.js">script>
<script>
    document.getElementById("btn").onclick = function () {
        var formData = {
            account: "",
            password: ""
        }
        let account = document.getElementById("account").value;
        formData.account = account;

        let password = document.getElementById("password").value;
        formData.password = password;
        console.log(formData);
        axios({
            method: 'post',
            url: 'http://localhost:80/login',
            data: formData
        }).then(function (resp) {
            console.log(resp)
            if (resp.data == "true") {
                window.alert("登录成功")
                console.log("ss")
            } else {
                console.log("ssas")
                window.alert("登录失败")
            }
        });
    }
script>

搜索同样问题在网上使用URLSearchParams但是没有用
后端打印的出这两个值为null，使用postMan访问后端login正常无错误，但是在html表单提交数据一直都是登录失败

希望能够指出语法错误或者多余字段指明

可以参考下：
https://blog.csdn.net/qq_45351419/article/details/106496192