Spot the bug in the sealed hierarchy

from Sealed classes
Java 25 LTS intermediate 4 min 1 issue to find

Find why this sealed hierarchy does not compile.

Java
public class Main {
    sealed interface Result permits Success, Failure {}
    record Success(String id) implements Result {}
    static class Failure implements Result {
        private final String reason;
        Failure(String reason) { this.reason = reason; }
        String reason() { return reason; }
    }
}
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