Document Tree Weird name behaviour

Users created a tree of documents and we use the tree to display the nesting on the page.

We have the following documents nested. Where the / seperates the actual documents on the wiki.

Somefolder /01 - some folder/Some other folder

When expanding the tree it works fine. When we you click the 01 - some folder. You wiill see a document 01 in the tree with all the subdocuments of 01 - some folder.