Attempt Number: 3
Error Message: Action not unique compared to other actions chosen from this state before. Choose a new action

Action Reasoning:
The next step in the plan is to board passenger p4 onto fast0 at floor n1. This action is necessary to move p4 closer to their goal destination on floor n3.

New State Description:
- **fast0**: A fast elevator at floor 1 (n1), now with 2 passengers (p1 and p4) and a capacity of 2.- **fast1**: A fast elevator at floor 0 (n0), with 0 passengers and a capacity of 2.- **slow0-0**: A slow elevator at floor 1 (n1), with 0 passengers and a capacity of 1.- **slow1-0**: A slow elevator at floor 3 (n3), with 0 passengers and a capacity of 1.- **p0**: On floor 1 (n1).- **p1**: Onboard fast0 at floor 1 (n1).- **p2**: On floor 2 (n2).- **p3**: On floor 0 (n0).- **p4**: Onboard fast0 at floor 1 (n1).- **p5**: On floor 3 (n3).

Action Chosen:
(board p4 fast0 n1 n1 n2)
