diff --git a/lnbits/bolt11.py b/lnbits/bolt11.py
index cc8c6040..cc841585 100644
--- a/lnbits/bolt11.py
+++ b/lnbits/bolt11.py
@@ -23,7 +23,6 @@ class Route(NamedTuple):
 
 class Invoice(object):
     payment_hash: str
-    checking_id: Optional[str] = None
     amount_msat: int = 0
     description: Optional[str] = None
     description_hash: Optional[str] = None
diff --git a/lnbits/wallets/fake.py b/lnbits/wallets/fake.py
index ba2956c5..3126ee46 100644
--- a/lnbits/wallets/fake.py
+++ b/lnbits/wallets/fake.py
@@ -80,11 +80,9 @@ class FakeWallet(Wallet):
 
     async def pay_invoice(self, bolt11: str, fee_limit_msat: int) -> PaymentResponse:
         invoice = decode(bolt11)
-        # TODO: no data here?
-        data: Dict = {"privkey": "missing"}
         if (
-            invoice.checking_id is not None
-            and invoice.checking_id[6:] == data["privkey"][:6]
+            hasattr(invoice, "checking_id")
+            and invoice.checking_id[6:] == data["privkey"][:6]  # type: ignore
         ):
             return PaymentResponse(True, invoice.payment_hash, 0)
         else: