Attempt Number: 2
Error Message: Action not unique compared to other actions chosen from this state before. Choose a new action

Action Reasoning:
To achieve the goal state, we need to place block 'd' on top of block 'c' which is already clear. This aligns with the goal of having block 'c' on the table with block 'd' on top of it.

New State Description:
Block 'a' is on the table and clear. Block 'c' is on top of block 'b' and is now supporting block 'd'. Block 'b' is on the table. Block 'd' is clear and on top of block 'c'. The hand is empty.

Action Chosen:
stack(d, c)
