Can't read post data in php api with slim 3

Question

I have a frontend in angular which consume API in php/slim3.

I call a php api with this post request :

return this.http.post<any>(API_URL + '/user', { data: userData });

With these form values : {name: "john", age: "25"}

in the api I have this code :

$app->post('/user', function (\Slim\Http\Request $request, \Slim\Http\Response $response) {
    $input = $request->getParams();
    $name = $input['name'];
    $age = $input["age"];
    echo json_encode($name);
}

When i run my app it returns null instead of name, but when i use postman with the same values it returns the good value.

I have tried with :

$input = $request->getParsedBody();

it's the same result.

What am i doing wrong ?

Thank you and sorry for my bad english...