diff --git a/src/game/tetris.py b/src/game/tetris.py
index 8e2682e..a6dfb10 100644
--- a/src/game/tetris.py
+++ b/src/game/tetris.py
@@ -280,7 +280,7 @@ def getPossibleBoards(self) -> list["Tetris"]:
                 if not moveBoard.isValidBlockPosition(moveBoard.block):
                     continue
 
-                moveBoard.prevBoard = copy.deepcopy(moveBoard.board)
+                moveBoard.prevBoard = moveBoard.deep_copy_list_of_lists(moveBoard.board)
                 if moveBoard not in possibleMoves:
                     possibleMoves.append(moveBoard)