You evaluate turn = 1 ? If so, you set turn to 2, making the next condition, evaluating if turn = 2 ? true.
Use 'else'.
if 1 ?
else
if 2 ?
else
if 3 ?
and so on.
Besides this obvious little error, i have no idea what the gamelogic is supposed to do. Sorry.
(link to the game: https://www.scirra.com/arcade/other-gam ... test-12492)