Collapse gift card option when the gift card is not enough

src/pretix/base/payment.py

@@ -985,6 +985,7 @@ class GiftCardPayment(BasePaymentProvider):
 
             remainder = cart['total'] - gc.value
             if remainder >= Decimal('0.00'):
+                del cs['payment']
                 messages.success(request, _("Your gift card has been applied, but {} still need to be paid. Please select a payment method.").format(
                     money_filter(remainder, self.event.currency)
                 ))