Photo returns to original position after being dragged to new position

According to a web search, I should be able to drag a photo into a new position in the Photos app that is native to iPhone.

When I do that, the thumbnail moves when I drag, but when I release, it simply moves back to its original position. At no point do the photos rearrange themselves to accommodate the new position of the dragged photo.

What am I doing wrong? I have the iPhone SE. According to Settings->General->About, the iPhone is running iOS 14.4

You can do this for albums, not Library (And only for albums you've created, not auto-generated ones like 'Recents').

To rearrange photos in an album: Tap Library button in bottom toolbar, select any album from "My Albums"; press on a photo thumbnail, drag it to the desired place and release. It will stay there.

Library is always presented in Date/Time order.