If this was a built-in list format, you can restore it by deleting the ListGal.dat file in your Windows user profile. Exit Word and search for the file in Windows Explorer. You have to enable the display of hidden files and folders first.


Note that the actual list isn't lost, if you had applied to text in some document. You can always retrieve it from the document.

__________________
Stefan Blom
Microsoft Word MVP

Microsoft 365 apps for business
Windows 11 Professional