Movieclip buttons linking to scenes

i have buttons inside of my movieclip that link to the different scenes. on the buttons i have the code
on (release) {
_root.gotoAndPlay(“bio”);
}

“bio” is the frame name of the first frame in the second scene. it works correctly when i click on it the first time. but if i click on that button again in the second scene, it goes to the third scene. and if i click on it again, it goes again to the second scene. also, when i click the button the second time and it goes to what would be a scene ahead of where it is supposed to be, when i click on the button that should bring it to the scene it is currently on, it goes to the next scene when it is supposed to be on the same scene.

any suggestions?