Hello! @sfn22
Welcome to the LastPass Community.
To move a subfolder to top level, you need to rename the folder, make sure that the new name is not duplicated or similar to other subfolders names, make sure to uncheck the optionAdd as a subfolder here, or if it is not checked, leave it unchecked, then save the changes and the sub folder will automatically convert to a top level folder
Check this guide for more information: How do I move a sub-folder up a level in my vault?
