Uploaded Images Not Showing Up In Order

Hi All ??

First off, great support forum. My question deals with uploading and organizing media within the stock wordpress gallery. I have named all my images “Blank_01.jpg” and so on all the way up to 30. When I go to uploaded them, I select all and upload. Then, then I go to the gallery they were placed in, they are not in numerical order: i.e. 1-30.jpg

Does anyone know why? Any help would be great. Thank you.