I am trying to use FormData to send user-entered data in a POST request with the fetch API. The problem is that when I create a new FormData object with the form that I've created, it keeps creating an empty object - no entries/keys/values

export class FinancialDocumentsController {
  constructor(private requestWithToken: <T>(config: AxiosRequestConfig) => Promise<AxiosResponse<T>>) {}
  
  public createFinancialDocumentsFilesUpload = ({ document, ...data }: CreateFinancialDocumentsFilesUploadReq) => {

    console.log(document, 'document');// {name: "36-2.png",size: 12251,type: "image/png"}

    const formData = new FormData();
    formData.append('document', document);
   
    console.log('formData', formData);//{empty}

    return this.requestWithToken<CreateFinancialDocumentsFilesUploadRes>({
      method: 'POST',
      url: FINANCIAL_DOCUMENTS_FILES_UPLOAD,
      data,
    });
  };
}