Problem with AJAX request

I did simple request

$.ajax({
url: "/go/",
method: "POST",
data: { value: "test" },
headers: {'X-Requested-With': 'XMLHttpRequest'},
});


Made router
$routes->post('go', [Owners::class, 'GetOffices']);


Controller Owner
public function GetOffices () {
return $this->response->setJson((new OwnerModel)->GetOffices());
}


And got next
POST http://localhost/go/ [HTTP/1.1 301 Moved Permanently 0ms]
GET http://localhost/go [HTTP/1.1 404 Not Found 57ms]

What goes wrong?
I need only one post requestб with json result