我如何清除Symfony中的查询字符串

In a Symfony 3 application i've a route for the search form with two controllers: one for a head/get request, and one for a post request. I need two controllers as searches can be shared.

Here's my problem: if a user comes to the site from a link with a query string, but then performs a post of the search form ... the query string from the original link he clicked always remains in the url, even after page reload.

So the question is: how can i clear out the query string? I've tried to remove all keys in the query ParameterBag of the request (which seems far-fetched as a way to solve this), but that didn't work.

Here's the code in my controller:

    $form = $this->buildSearchForm();
    $form->handleRequest($request);
    $searchTerm = $form->get('search')->getData();
    $types = $this->getTypes($form);
    $query = $this->assembleQuery($form);

    return $this->render("search/zoekpagina.html.twig", array(
        "distance" => $form->get('distance')->getData(),
        "form" => $form->createView(),
        "results" => $ESquery->searchByType($types, $query, $searchTerm),
        "searchTerm" => $searchTerm,
        "filters" => true,
    ));