WP REST API GET Method Works But Not The POST Method

Question

Your apiFetch() usage is correct, but you’re getting the “No route was found” error because of the 'method' => 'POST' part which should actually use methods and not method. (Note that an endpoint can allow one or more HTTP methods)

So when it’s method, it’s not used and thus the HTTP method defaults to GET only.

And all you need to do is use 'methods' => 'POST' (or 'methods' => 'GET,POST' if you wanted to allow both GET and POST methods), and the error would be gone.