exported list order changed

I used to export the latest subscriber's list every week through the page "admin/people/simplenews/export", it was showing all the emails from the oldest to the newest order, so I can pickup those latest subscribers through the end of the list.

But today I noticed it suddenly changed, it's exporting the list and showing on the a-z order, so I can't find out who is the latest subscribers, I didn't do anything on the system, I don't know why and how the system changed on itself.

Please advise how can I show all the subscribers in the oldest to the newest order, Thank you