I suggest that you update the top node to use different messages for the "open" die and the "tie" die. Something as simple as changing "Couldn't open" to "Couldn't tie". Also, you might want to add a message after the close statement to show explicitly that you're getting past that stage.

Some people may go through your code to find which die is at line 19, but clearly the first few posters here didn't. It's all about helping people highlight what's going wrong. (Though I think that my reply elsewhere answers what's going wrong)