# How to use a redirect with Form builder to prevent double submission It is common for form submission HTTP responses to be a `302 Found` temporary redirection to a new page. By default `wagtail.contrib.forms.models.FormPage` success responses don't do this, meaning there is a risk that users will refresh the success page and re-submit their information. Instead of rendering the `render_landing_page` content in the POST response, we will redirect to a `route` of the `FormPage` instance at a child URL path. The content will still be managed within the same form page's admin. This approach uses the additional contrib module `wagtail.contrib.routable_page`. An alternative approach is to redirect to an entirely different page, which does not require the `routable_page` module. See [](form_builder_custom_landing_page_redirect). Make sure `"wagtail.contrib.routable_page"` is added to `INSTALLED_APPS`, see [](routable_page_mixin) documentation. ```python from django.shortcuts import redirect from wagtail.contrib.forms.models import AbstractEmailForm from wagtail.contrib.routable_page.models import RoutablePageMixin, path class FormPage(RoutablePageMixin, AbstractEmailForm): # fields, content_panels, … @path("") def index_route(self, request, *args, **kwargs): """Serve the form, and validate it on POST""" return super(AbstractEmailForm, self).serve(request, *args, **kwargs) def render_landing_page(self, request, form_submission, *args, **kwargs): """Redirect instead to self.thank_you route""" url = self.reverse_subpage("thank_you") # If a form_submission instance is available, append the ID to URL. if form_submission: url += "?id=%s" % form_submission.id return redirect(self.url + url, permanent=False) @path("thank-you/") def thank_you(self, request): """Return the superclass's landing page, after redirect.""" form_submission = None try: submission_id = int(request.GET["id"]) except (KeyError, TypeError): pass else: submission_class = self.get_submission_class() try: form_submission = submission_class.objects.get(id=submission_id) except submission_class.DoesNotExist: pass return super().render_landing_page(request, form_submission) ```