nav button not working

Hi,

I have a basic nav menu consisting of four buttons all of which are coded

on (release) {

  gotoAndPlay(the frame number);

}

I have a stop in the frame prior to each of the landing pages.

My problem is that when I click on the button to go to the final frame content, (frame 40),  the content appears briefly on release but then immediately jumps to frame 1 again.

This is very likely a very simple fix but am pressed for time so any help appreciated.