Thanks for the kind words. I did hit this error a couple of times when testing out the code that would ultimately live in the tutorial. If I remember correctly, I found that this happened when the token wasn't actually minted. Because we're running on an emulator, it's harder to know for sure if the bug is simply just from emulator restarts or not. But if you keep hitting this issue, I'd try writing the whole things in the Flow Playground and see if it works for you.