AngularJs API post file to the .net core app endpoint file parameter is null

I am using ald angularJs and trying upload file and do API call, API is a .net core app, I can see request using breakpoint in the API but parameter is comes null always.

here is the angularJs code

 vm.uploadMotorFactor = function () {
   let uploadUrl = `/api/Membership/UploadMotorFactor`;

   let fileInput = document.getElementById('motorFactorFile');
   let file = fileInput.files[0];

   if (!file) {
     alert("Please select a CSV file to upload.");
     return;
   }

   let formData = new FormData();
   formData.append('file', file); // Matches the property name in ImportFileDataRequest

   $http.post(uploadUrl, formData, {
     headers: { 'Content-Type': undefined }, // Let the browser set the correct multipart boundary
     transformRequest: angular.identity
   }).then(response => {
     alert('File uploaded successfully!');
     fileInput.value = ''; // Clear the file input after successful upload
   }).catch(error => {
     console.error('Error uploading file:', error);
     alert('File upload failed.');
   });
 };

this is my API endpoint

 [HttpPost]
 public async Task<IActionResult> UploadMotorFactor([FromForm] IFormFile file)
 {
     try
     {
         return file != null ? Ok() : StatusCode(StatusCodes.Status500InternalServerError);
        
     }
     catch (Exception e)
     {
         _logger.LogError(e, "Failed to download Motor factor");
         return StatusCode(StatusCodes.Status500InternalServerError);
     }
 }

I used 'Content-Type', 'multipart/form-data' as well but the result is the same, what I am missing here?

it is an old angularjs and looks like this:

<input type="file" id="motorFactorFile"  />
 <button class="btn btn-success" ng click="vm.uploadMotorFactor()">Upload</button>

this is the js file:

const mycommadashboard = angular.module("umbraco");

mycommadashboard.controller("MyDashboardController",
  function ($scope, $http, $timeout, Upload) {
    let vm = this;
    vm.uploadMotorFactor = function () {
      
    };

  });

Here is the solution https://our.umbraco.com/forum/extending-umbraco-and-using-the-api/81065-file-upload-in-backoffice-custom-section

 let fileInput = document.getElementById(`ImageFile`);
  let file = fileInput.files[0];

$http({
    method: 'POST',
    url: "/umbraco/backoffice/api/myController/Create",
    headers: { 'Content-Type': undefined }, // Let the browser set multipart/form-data boundaries
    transformRequest: function () {
      var formData = new FormData();
      if (file) {
        formData.append("file", file);
      }
      formData.append("competition", JSON.stringify(vm.competition)); // Send competition object as string
      return formData;
    }
  })

this is an .net API action method

[HttpPost]
public async Task<IActionResult> Create([FromForm] IFormFile file, [FromForm] string competition)
{
 var competitionData = JsonConvert.DeserializeObject<CompetitionRequest>(competition);
// do service call
}