[Plugin: Redirection] One redirect not working

Love this plugin – saved me loads of work having moved a site from DotNetNuke to WP.

I have just one redirect that seems to fail:
It should go to https://www.mysite.com/category-name – in the log it is going to https://www.mysite.com/category-namecategory-name

I get an ‘Internet Explorer cannot display the web page’ and a ‘Diagnose Connection Problems’ button

When I type https://www.mysite.com/category-name directly into browser the same error occurs but I cannot find a redirect I have set up that would cause this.
All other redirects and cateogories work fine.
What am I doing wrong.
Thanks