diff --git a/README.md b/README.md
index 85de1e0..723edf3 100644
--- a/README.md
+++ b/README.md
@@ -75,7 +75,7 @@ poetry run mypy src/ --check-untyped-defs
 
 # Running test
 poetry run coverage run -m pytest  # all tests
-poetry run coverage run -m pytest -s tests/presentation/test_server.py # specific file
+poetry run coverage run -m pytest tests/presentation/test_server.py # specific file
 poetry run coverage run -m pytest tests/presentation/test_worker.py -k 'test_should_select_by_account_id' # specific test
 ```
 
diff --git a/src/core/helpers.py b/src/core/helpers.py
index 9b59b92..40b481d 100644
--- a/src/core/helpers.py
+++ b/src/core/helpers.py
@@ -3,10 +3,7 @@
 
 
 def is_valid_uuid(value: Any):
-    try:
-        return uuid.UUID(str(value))
-    except ValueError as exc:
-        raise exc
+    return uuid.UUID(str(value))
 
 
 class FlowPostPaidError(Exception):
@@ -17,3 +14,8 @@ def __init__(self):
 class FlowPrePaidError(Exception):
     def __init__(self):
         super().__init__("This flow should only be used by pre-paid plan")
+
+
+class InvoicePostPaidError(Exception):
+    def __init__(self):
+        super().__init__("Every post-paid user should have at least a draft invoice")
diff --git a/src/core/repository/account.py b/src/core/repository/account.py
index 48602a4..04cbc46 100644
--- a/src/core/repository/account.py
+++ b/src/core/repository/account.py
@@ -102,7 +102,6 @@ def change_type(self, account_id_: UUID, type_: AccountType) -> None:
 
     def by_subscription_period(self) -> List[Account]:
         today = datetime.datetime.today()
-        should_be_deleted = subscription_table.c.deleted_at is None
         query_subscription = (
             select(account_table)
             .join(
@@ -110,8 +109,8 @@ def by_subscription_period(self) -> List[Account]:
                 account_table.c.id == subscription_table.c.account_id,
             )
             .where(
-                extract("day", subscription_table.c.created_at)
-                == today.day & should_be_deleted,
+                extract("day", subscription_table.c.created_at) == today.day,
+                subscription_table.c.deleted_at.__eq__(None),
             )
         )
         rows = self.session.execute(query_subscription).all()
diff --git a/src/core/repository/billing.py b/src/core/repository/billing.py
index 121e5cf..5555cf9 100644
--- a/src/core/repository/billing.py
+++ b/src/core/repository/billing.py
@@ -12,6 +12,7 @@
 from src.core.usecase.driven.billing.billing_fetch_user import BillingFetchUser
 from src.core.usecase.driven.billing.billing_fetching_invoice import (
     BillingFetchingInvoice,
+    NoDraftInvoiceFound,
 )
 from src.core.usecase.driven.billing.billing_updating_invoice import (
     BillingUpdatingInvoice,
@@ -33,7 +34,7 @@ def get_current(self, external_id: UUID) -> Invoice:
         )
         json = resp.json()
         if json["status"] != "draft":
-            raise Exception("No invoice on status draft was fetched")
+            raise NoDraftInvoiceFound("No invoice on status draft was fetched")
         return Invoice(
             json["id"],
             external_id,
@@ -52,7 +53,7 @@ def add_item(self, external_id: UUID, item_list: List[InvoiceItem]) -> Invoice:
                 is_valid_uuid(json["id"]),
                 is_valid_uuid(json["user_id"]),
                 json["status"],
-                datetime.datetime.strptime(json["created_at"], "%d/%m/%y"),
+                datetime.datetime.strptime(json["created_at"], "%Y-%m-%d"),
             )
             return invoice
         except HTTPError as exc:
diff --git a/src/core/usecase/charge_debit.py b/src/core/usecase/charge_debit.py
index cdccfd6..96436e5 100644
--- a/src/core/usecase/charge_debit.py
+++ b/src/core/usecase/charge_debit.py
@@ -1,4 +1,5 @@
 from src.core.entity.account import Account, AccountType
+from src.core.helpers import InvoicePostPaidError
 from src.core.usecase.driven.billing.billing_fetching_invoice import (
     BillingFetchingInvoice,
 )
@@ -34,6 +35,6 @@ def _charge_single_user(self, user: Account) -> None:
             return
         current_invoice = self.billing_fetching_invoice.get_current(user.external_id)
         if current_invoice.status != "draft":
-            raise Exception("Every post-paid user should have at least a draft invoice")
+            raise InvoicePostPaidError()
         self.billing_updating_invoice.charge(current_invoice.id)
         return None
diff --git a/src/core/usecase/driven/billing/billing_fetching_invoice.py b/src/core/usecase/driven/billing/billing_fetching_invoice.py
index 57021b8..a0f0780 100644
--- a/src/core/usecase/driven/billing/billing_fetching_invoice.py
+++ b/src/core/usecase/driven/billing/billing_fetching_invoice.py
@@ -4,6 +4,10 @@
 from src.core.entity.billing import Invoice
 
 
+class NoDraftInvoiceFound(Exception):
+    "Raised when account does not exists on database"
+
+
 class BillingFetchingInvoice(metaclass=ABCMeta):
     @abstractmethod
     def get_current(self, external_id: UUID) -> Invoice:
diff --git a/src/presentation/worker.py b/src/presentation/worker.py
index e1febc8..62e992a 100644
--- a/src/presentation/worker.py
+++ b/src/presentation/worker.py
@@ -35,7 +35,10 @@ def post_paid_automation_charge():
                 billing_updating_invoice.charge(invoice.id)
 
 
+# Listing all jobs
 schedule.every(1).day.do(post_paid_automation_charge)
-while True:
-    schedule.run_pending()
-    time.sleep(1)
+
+if __name__ == "__main__":
+    while True:
+        schedule.run_pending()
+        time.sleep(1)
diff --git a/tests/factory/helpers.py b/tests/factory/helpers.py
index b6896e7..d137b6e 100644
--- a/tests/factory/helpers.py
+++ b/tests/factory/helpers.py
@@ -1,4 +1,6 @@
+import datetime
 from copy import deepcopy
+from typing import Optional
 from uuid import UUID
 
 from sqlalchemy import delete, insert, select
@@ -15,32 +17,38 @@
 
 
 # ACCOUNT
-def create_account(session: Session, external_id: UUID, type_: AccountType):
+def create_account(
+    session: Session,
+    external_id: UUID,
+    type_: AccountType,
+    created_at: Optional[datetime.datetime] = None,
+):
     account_insert_line = (
         insert(account_table)
-        .values(external_id=external_id, type=type_)
+        .values(
+            external_id=external_id,
+            type=type_,
+            created_at=(
+                created_at if created_at is not None else datetime.datetime.now()
+            ),
+        )
         .returning(
             account_table.c.id, account_table.c.created_at, account_table.c.deleted_at
         )
     )
     cursor_user = session.execute(account_insert_line).first()
+    session.commit()
     if cursor_user is None:
         raise SystemError("test: create_account something went wrong")
-    (id_, created_at, deleted_at) = deepcopy(cursor_user)
-    subscription_insert_line = (
-        insert(subscription_table)
-        .values(account_id=id_, type=type_)
-        .returning(
-            subscription_table.c.id,
-            subscription_table.c.created_at,
-            subscription_table.c.deleted_at,
-        )
+    (id_, created_at_, deleted_at_) = deepcopy(cursor_user)
+    subscription_insert_line = insert(subscription_table).values(
+        account_id=id_, type=type_
     )
-    cursor_subscription = session.execute(subscription_insert_line).first()
+    cursor_subscription = session.execute(subscription_insert_line)
     if cursor_subscription is None:
         raise SystemError("test: create_account something went wrong")
     session.commit()
-    return Account(id_, external_id, type_, created_at, deleted_at)
+    return Account(id_, external_id, type_, created_at_, deleted_at_)
 
 
 def delete_account(session: Session, id_: UUID):
diff --git a/tests/presentation/_test_worker.py b/tests/presentation/test_worker.py
similarity index 80%
rename from tests/presentation/_test_worker.py
rename to tests/presentation/test_worker.py
index 16008e1..c9f1cb7 100644
--- a/tests/presentation/_test_worker.py
+++ b/tests/presentation/test_worker.py
@@ -18,20 +18,22 @@
 
 @responses.activate
 def test_worker_post_paid_automation_charge(session: Session):
-    account = create_account(session, uuid4(), AccountType.POST_PAID)
+    one_month_ago = datetime.datetime.now() - datetime.timedelta(days=30)
+    account = create_account(session, uuid4(), AccountType.POST_PAID, one_month_ago)
     event = get_event(session)
     transaction1 = create_transaction(session, account.id, -event.price, "t1", event.id)
     transaction2 = create_transaction(session, account.id, -event.price, "t2", event.id)
     transaction3 = create_transaction(session, account.id, -event.price, "t3", event.id)
 
+
     responses.add(
         responses.POST,
         f"{EnvVars.BILLING_HOST}/invoice",
         status=200,
         json={
-            "id": uuid4(),
-            "user_id": uuid4(),
-            "status": "draft",
+            "id": uuid4().__str__(),
+            "user_id": uuid4().__str__(),
+            "status": "Draft",
             "created_at": datetime.date.today().__str__(),
         },
     )
@@ -40,10 +42,10 @@ def test_worker_post_paid_automation_charge(session: Session):
         f"{EnvVars.BILLING_HOST}/charge",
         status=200,
         json={
-            "id": uuid4(),
-            "invoice_id": uuid4(),
-            "status": "charge",
-            "payment_method_id": uuid4(),
+            "id": uuid4().__str__(),
+            "invoice_id": uuid4().__str__(),
+            "status": "Progress",
+            "payment_method_id": uuid4().__str__(),
             "created_at": datetime.date.today().__str__(),
         },
     )