Ajax Not Working – DATA CANT BE IDENTIFIED

student_id having a value of 0001. It shows the error

“Uncaught ReferenceError: studentId is not defined”

$.ajax({
    url: "student_info.php",
    method: "post",
    data: {
      studentId: student_id
    },
    success: function (data, status) {
      console.log(studentId);
    },
  });

console.log should display the value of ‘0001’.