Sometimes CCCallFuncN is not fired in Cocos2d

Question

I am noticing that sometimes the CCCallFuncN callback function is not triggered. I am not sure why is this behavior?

[alphabetToFind stopAllActions]; 

        id disappear = [CCFadeTo actionWithDuration:.5 opacity:0]; 
        id actionMoveDone = [CCCallFuncN actionWithTarget:self selector:@selector(removeAlphabetToFindFromView:)];
        id actionScale = [CCScaleBy actionWithDuration:0.6 scaleX:10 scaleY:10]; 
        id moveTo = [CCMoveTo actionWithDuration:0.6 position:ccp(windowSize.width/2, windowSize.height/2)]; 


        [alphabetToFind runAction:[CCSequence actions:moveTo,actionScale,disappear,actionMoveDone, nil]];