Reject of PO Release Strategey

Dears,

Please i want to handle the cancaletion of Po release by sending mail to the initiator but it doesn't work.

I make each tasks TS20000167 & TS20000168  As general tasks

and use AC20000027 in TS20000166 to get the approval and it works fine and it transfers from approval to another approval secussefully

but when i cancel it excute the TS20000168 not TS20000167 .

Note : i copied the standard WS20000075 .

i searched but i cant solve this issue