diff --git a/src/pretix/base/forms.py b/src/pretix/base/forms.py
index e6ba80653b..a24e89fc73 100644
--- a/src/pretix/base/forms.py
+++ b/src/pretix/base/forms.py
@@ -75,8 +75,8 @@ class SettingsForm(forms.Form):
     This form is meant to be used for modifying Event- or OrganizerSettings
     """
     BOOL_CHOICES = (
-        ('True', _('enabled')),
         ('False', _('disabled')),
+        ('True', _('enabled')),
     )
 
     def __init__(self, *args, **kwargs):
diff --git a/src/pretix/base/payment.py b/src/pretix/base/payment.py
index aa3ff5dbb6..d26dc61edf 100644
--- a/src/pretix/base/payment.py
+++ b/src/pretix/base/payment.py
@@ -98,10 +98,9 @@ class BasePaymentProvider:
         """
         return OrderedDict([
             ('_enabled',
-             forms.ChoiceField(
+             forms.BooleanField(
                  label=_('Enable payment method'),
                  required=False,
-                 choices=SettingsForm.BOOL_CHOICES,
              )),
             ('_fee_abs',
              forms.DecimalField(
diff --git a/src/pretix/base/ticketoutput.py b/src/pretix/base/ticketoutput.py
index 752675a102..f12001d6fd 100644
--- a/src/pretix/base/ticketoutput.py
+++ b/src/pretix/base/ticketoutput.py
@@ -86,10 +86,9 @@ class BaseTicketOutput:
         """
         return OrderedDict([
             ('_enabled',
-             forms.ChoiceField(
+             forms.BooleanField(
                  label=_('Enable output'),
                  required=False,
-                 choices=SettingsForm.BOOL_CHOICES,
              )),
         ])
 
diff --git a/src/pretix/presale/views/checkout.py b/src/pretix/presale/views/checkout.py
index ac4d135c3a..324e397f5f 100644
--- a/src/pretix/presale/views/checkout.py
+++ b/src/pretix/presale/views/checkout.py
@@ -174,6 +174,8 @@ class PaymentDetails(EventViewMixin, CartDisplayMixin, EventLoginRequiredMixin,
                     return redirect(self.get_confirm_url())
                 else:
                     return self.get(request, *args, **kwargs)
+        messages.error(self.request, _("Please select a payment method."))
+        return self.get(request, *args, **kwargs)
 
     def get_context_data(self, **kwargs):
         ctx = super().get_context_data(**kwargs)