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

Action Reasoning:
The next action in the plan is to move fast1 from floor n4 to floor n5, so passengers p2 and p3 can reach their destination.

New State Description:
- fast0: At floor n0, 0/2 passengers.- fast1: At floor n5, 2/2 passengers (p2 and p3 on board).- slow0-0: At floor n2, 0/1 passengers.- p0: On floor n4.- p1: On floor n1.- p2: On board fast1.- p3: On board fast1.- p4: On floor n2.- p5: On floor n5.- p6: On floor n2.

Action Chosen:
(move-up-fast fast1 n4 n5)
