Laravel txt file is not uploading

In Laravel 5, I want to upload files like pdf, jpeg, and also txt files etc. I see the uploading is working well with the file extension except .txt files. My code is as under;

$validator = Validator::make($request->all(), [
  'itemImage' => 'mimes:jpeg,jpg,gif,png,bmp,svg,doc,docx,odt,xls,xlsx,pdf,txt |max:4096'
]);

I also tried by replacing the txt as text/plain but got the same problem.

via Chebli Mohamed