When I try to change the item type in My Library online, I can select a new item type in the pulldown, but then the page hangs on Save every time. I do not change any other fields, just Item Type. Why is this happening?

I need this to work because I'm always writing on my iPad now and need to edit my items online as I add footnotes. I'm thinking of making a shortcut in the Shortcuts app just to change the Item Type but I'd like to understand the problem better before spending time on the shortcut. Thanks!