SharePoint Workflow 2013

I have a list workflow that triggers when a Topic is changed. Finds the Folder with the same Topic name by it's ID.   I can't find a way to rename the folder to equal the Topic.

I used  Query List (filter  by Folder content type) but doesn't work.  I also used the update item and it still doesn't work.

Perhaps Call Web Service UpdateListItems but I'm stuck at the field "Updates (xml)".

Can someone please give me a hand?

Thanks,

Monica