Welcome to the Make community!
Please see this duplicate topic on Wordpress tags/categories/custom taxonomy:
- About Wordpress Tags - Automation Wordpress Tags - #3 by samliew
- A term with the name provided already exists in this taxonomy. (error code: term_exists) - #2 by samliew
Hope this helps! Let me know if there are any further questions or issues.
— @samliew
P.S.: Investing some effort into the Make Academy will save you lots of time and frustration using Make.