diff --git a/mock/nft_mock.go b/mock/nft_mock.go
index cda4033..b005ba0 100644
--- a/mock/nft_mock.go
+++ b/mock/nft_mock.go
@@ -40,13 +40,15 @@ func (m *MockNFTDetector) IsNFTTransaction(tx *types.Transaction) bool {
 		return m.IsNFTTransactionFunc(tx)
 	}
 
-	// Default implementation using known contracts
 	if tx.To() == nil {
 		return false
 	}
 
-	isContract, exists := m.knownContracts.Load(*tx.To())
-	return exists && isContract.(bool)
+	if val, exists := m.knownContracts.Load(*tx.To()); exists {
+		return val.(bool)
+	}
+
+	return false
 }
 
 // Helper methods for testing
diff --git a/mock/nft_mock_test.go b/mock/nft_mock_test.go
index 90b9f78..7267f8b 100644
--- a/mock/nft_mock_test.go
+++ b/mock/nft_mock_test.go
@@ -17,15 +17,27 @@ func TestMockNFTDetector(t *testing.T) {
 		address := common.HexToAddress("0xBAYC")
 		detector.AddKnownContract(address)
 
+		// Create transaction to the known contract address
 		tx := types.NewTransaction(
 			0,
-			address, // Remove & operator, use Address directly
+			address,
 			big.NewInt(0),
 			21000,
 			big.NewInt(1),
 			nil,
 		)
+
+		// Add debug assertions
+		toAddr := tx.To()
+		if toAddr == nil {
+			t.Fatal("Transaction To address is nil")
+		}
+
+		// Verify the addresses match
+		assert.Equal(t, address, *toAddr, "Transaction address should match known contract")
+
+		// Check if transaction is detected as NFT
 		result := detector.IsNFTTransaction(tx)
-		assert.True(t, result)
+		assert.True(t, result, "Transaction to known NFT contract address should return true")
 	})
 }