WooCommerce API JSON/HTML

I am running an ecommerce store using WooCommerce and trying to connect TaxJar to handle all my sales tax calculations.

In order to connect, TaxJar needs to access the WooCommerce API, located at (for my site) https://www.7j1fashion.com/wc-api/v2. There seems to be some kind of issue, and after speaking with the folks at TaxJar, they said the API is responding with HTML content type instead of JSON. They thought a plugin might be caching the endpoint, but I disabled all plugins and I’m still having the same problem.

Has anyone had this experience before, or have any insight to share? Thanks in advance.