问ajax post请求contentType导致“错误请求”错误

EN

$.ajax({
  type: 'POST',
  url: posturl,
  data: {
    authenticity_token: $('[name="csrf-token"]')[0].content,
    msg_time: msg_time,
    sender: sender,
    sender_name: sender_name,
    body: msgbody,
  },
  success: function (res) {
    console.log(res);
  },
  error: function (err) {
    console.log(err);
  },
});