How to resolve error 405.0 - Method Not Allowed?

Question

IIS

Raised the IIS server on the local machine. Raised a site on it and attached WebApi to it. After accessing the WebApi on the site, a 405 error Method Not Allowed crashes.
In more detail, on the site in the index page there is a simple form that sends data to the server and receives a response from the server. The data comes to the server and from the server comes to the page (caught by breakpoints), but after receiving the data, the page immediately opens the error “HTTP Error 405.0 - Method Not Allowed. The page you are looking for cannot be displayed because an invalid method (HTTP command) is being used."
What could be the problem and how to fix it?

Answer 1

Google advises to do so what happens?