diff --git a/lnbits/wallets/spark.py b/lnbits/wallets/spark.py
index 633948ddf..5f5a00fef 100644
--- a/lnbits/wallets/spark.py
+++ b/lnbits/wallets/spark.py
@@ -200,7 +200,10 @@ class SparkWallet(Wallet):
         if r["pays"][0]["payment_hash"] == checking_id:
             status = r["pays"][0]["status"]
             if status == "complete":
-                fee_msat = -(int(r["pays"][0]["amount_sent_msat"][0:-4]) - int(r["pays"][0]["amount_msat"][0:-4]))
+                fee_msat = -(
+                    int(r["pays"][0]["amount_sent_msat"][0:-4])
+                    - int(r["pays"][0]["amount_msat"][0:-4])
+                )
                 return PaymentStatus(True, fee_msat, r["pays"][0]["preimage"])
             elif status == "failed":
                 return PaymentStatus(False)