Microsoft

So what do you need to do then? You need to create a completely new order hint value from scratch. If you look at the official documentation linked above, you’ll notice that to add an item as the last item on a list, you need to take the previous item order hint and then just add ‘ !’ (whitespace and an exclamation mark). When there are no items yet on the list, the previous order hint is empty, and hence the order hint value of the very first item is simply ‘ !’.

When SharePoint is enabled for sensitivity labels, you can configure a default label for document libraries. Then, any new files uploaded to that library, or existing files edited in the library will have that label applied if they don't already have a sensitivity label, or they have a sensitivity label but with lower priority.