问为什么我的api更新代码不能在slim php框架中工作?

EN

 /* *
 * URL: http://localhost/StudentApp/v1/submitassignment/<assignment_id>
 * Parameters: none
 * Authorization: Put API Key in Request Header
 * Method: PUT
 * */

$app->put('/submitassignment/:id',  function($id) use ($app){
    $db = new DbOperation();
    $result = $db->updateAssignment($id);
    $response = array();
    if($result){
        $response['error'] = false;
        $response['message'] = "Assignment submitted successfully";
    }else{
        $response['error'] = true;
        $response['message'] = "Could not submit assignment";
    }
    echoResponse(200,$response);
});

//Method to update assignment status
    public function updateAssignment($id){
        $stmt = $this->con->prepare("UPDATE firm SET name = ? WHERE id=?");
        $stmt->bind_param("si", $name, $id);
        $result = $stmt->execute();
        $stmt->close();
        if($result){
            return true;
        }
        return false;
    }