Search and Replace Adds Tag Folder

I am experiencing an issue where I am attempting to perform a search and replace on a tag name and when I press replace, what ends up happening is the tag will remain unchanged, but is placed in a folder with the name. For example:

Search: old_tag
Finds a tag of path: [default]folder/old_tag
Replace: new
When you hit the replace button you then get a tag with the path:[default]folder/new_tag/old_tag