plugins route post controller? I am developing a custom authentication plugin for Craft 3. But I can't route to my Controller via POST request with my login form. Request via GET work
Although your question is lacking in detail, here is a shot at helping you track down the issue. The fact that GET requests are working but POST requests are not, your form is likely missing a CSRF token. You can add it to your form using the following twig code:

&lt;form method="post" action=""&gt;

   {{ csrfInput() }}


If your POST request is coming through as an AJAX request then you can create and submit a CSRF token as described in this answer.