Uncaught TypeError: The first argument must be one of type string, Buffer, ArrayBuffer, Array, or Array-like Object. Received type object

I am trying to upload images to a s3 bucket from react app. It's purely frontend and I am not passing any to/from backend. This is my function that uploads file:

 function uploadfile(fileName, selectedfile) {
const params = {
  Bucket: "mks-sample-bucket",
  Key: fileName,
  Body: Buffer.from(selectedFile, "binary"),
  ContentType: file.type,
};
return bucket.upload(params, function (err, data) {
  if (err) {
    console.log("There was an error uploading your file: ", err);
    return false;
  }
  console.log("Successfully uploaded file.", data);
  return true;
});

}

This is the error I am getting "Uncaught TypeError: The first argument must be one of type string, Buffer, ArrayBuffer, Array, or Array-like Object. Received type object".

I am not sure why I am getting this issue.