Attempt Number: 4
Error Message: Action not unique compared to other actions chosen from this state before. Choose a new action

Action Reasoning:
Since fast0 is at floor 1 and can hold one more passenger, I will board p4 to fast0. This aligns with the next step in the desired plan.

New State Description:
- **fast0**: Fast elevator currently at floor 1 (n1), with passengers p1 and p4 onboard, capacity of 2.- **fast1**: Fast elevator at floor 0 (n0), with 0 passengers, capacity of 2.- **slow0-0**: Slow elevator at floor 1 (n1), with 0 passengers, capacity of 1.- **slow1-0**: Slow elevator at floor 3 (n3), with 0 passengers, 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)
