Maybe I did not know how to search, but I didn´t find the answer to my question.
I know it´s simple but I`m stuck.
I have a MC with code:

on(release){
gotoAndStop(2);
}

It´s working fine.

Inside frame 2 of MC I put a button with code:

on(release){
gotoAndStop(1);
}

This should take me to 1st frame of MC, right?

But the button doesn´t work.
Nothing happens.
I changed its color when mouse is over and down to check if the button has functionality but it remains as it is. No color change, although the mouse pointer changes to hand when it hits the button area.

Strange is If I change the code in MC to:

on(release){
play();
}

I go to MC`s frame 2 as well, but this time the button works fine.

Any idea?

Thanks in advance.