Custom cursor duplicating

Right, i will shortly describe the situation: I have two layers each has 2 frames. the upper one is “cursor” and the lower one is “buttons”. on buttons both of the frames are keyframes. on cursor i have a custom cursor. on frame 2 i have a button on buttons. the button has this code:
[AS]on(release){
prevFrame();
}[/AS]

the problem: when the frames shift the cursor is somehow duplicated and there are two of them- one is standing in one place but the other is being dragged.

Anyone, help? :m: