diff --git a/registrasion/tests/test_voucher.py b/registrasion/tests/test_voucher.py
index e3ac0d0d3699e3007926a5d0b562154067372f09..a8686fb1d7c3535edad075be0c0e0b5788318e77 100644
--- a/registrasion/tests/test_voucher.py
+++ b/registrasion/tests/test_voucher.py
@@ -34,8 +34,8 @@ class VoucherTestCases(RegistrationCartTestCase):
         # user 2 should be able to apply voucher
         self.add_timedelta(rego.Voucher.RESERVATION_DURATION * 2)
         cart_2.apply_voucher(voucher.code)
-        cart_2.cart.active = False
-        cart_2.cart.save()
+
+        cart_2.next_cart()
 
         # After the reservation duration, even though the voucher has applied,
         # it exceeds the number of vouchers available.
@@ -125,8 +125,8 @@ class VoucherTestCases(RegistrationCartTestCase):
         current_cart = TestingCartController.for_user(self.USER_1)
         current_cart.apply_voucher(voucher.code)
 
-        inv = InvoiceController.for_cart(current_cart.cart)
-        inv.pay("Hello!", inv.invoice.value)
+
+        current_cart.next_cart()
 
         current_cart = TestingCartController.for_user(self.USER_1)
 
@@ -139,9 +139,11 @@ class VoucherTestCases(RegistrationCartTestCase):
         voucher = self.new_voucher(limit=2)
         current_cart = TestingCartController.for_user(self.USER_1)
         current_cart.apply_voucher(voucher.code)
+        current_cart.add_to_cart(self.PROD_1, 1)
 
         inv = InvoiceController.for_cart(current_cart.cart)
-        inv.pay("Hello!", inv.invoice.value)
+        if not inv.invoice.paid:
+            inv.pay("Hello!", inv.invoice.value)
 
         current_cart = TestingCartController.for_user(self.USER_1)
         with self.assertRaises(ValidationError):