Rust printed this

thread 'main' panicked at 'called `Option::unwrap()` on a `None` value'

What it meansYour code called unwrap on an Option that held None, so there was no value to extract and the thread panicked at runtime.

The first thing to checkFind the unwrap from the panic location, then handle None with match, if let, unwrap_or, or the ? operator instead of assuming a value exists.