Fix: The WordPress REST API

The best way to check is to visit this URL: https://yoursite.com/wp-json. If you see some information which seems related to your WordPress REST API, it works. If you see something, it means that, at least, your WordPress REST API is enabled. Otherwise, that’s not working, and you will need to understand why.

Visit your Settings > Permalinks. Make sure Plain is not selected. Usually, Post Name is the best choice. Even if everything is fine, click on Save Changes. That will rewrite/repair your .htaccess.