Laravel - .TXT file Being Converted to .BIN on Upload

I'm not quite sure where to look, so I can't even tell if this is an issue with the server or with the Laravel project itself, but on one of my models, if I upload a .TXT file attached to a record, it shows up on the server as a .BIN file.

There isn't really anything to the upload controller action itself:

    if($request->paymentAttachment){
    $payment->attachment = Storage::putFile('public/payments', $request->file('paymentAttachment'));
    }

So I'm not sure where the conversion might be happening. If there are any ideas, I'd greatly appreciate them.

Thanks

via Chebli Mohamed