Ever since Gutenberg Editor replaced the classic WordPress editor in the WordPress 5.0, content creators are loving every bit of it. It has truly made editing fun with innovative and user-friendly features to offer.
This new editor is a part of WordPress 5.0+ updates and uses REST API as its interface program. Therefore, all new posts creation, editing, and publishing are performed via the REST API.
But, even after all the hype, quite a few people were disappointed by Gutenberg's (latest version) inability to let them save their posts.
This happens when something is coming in the way of REST API by blocking or disabling it.
Consequently, WordPress will fail to work as an effective Content Management System as it will not be able to build an unbroken communication link with other web applications using REST API.