Changing events with duplicateMovie

I want a MovieClip to be ‘replaced’ when the original is moved but don’t want the moved clip to be duplicated when it is moved again. The scenario is to be able to take coins from an “endless pile”.
I’ve used the Behaviours menu to make the MovieClip duplicate when it is clicked and dragged. Unfortunately for me in this case, the duplicate MovieClip contains the events of the original, and so each coin can be duplicated, not just the original one. Can someone give me an idea of how to change the properties of the duplicated movieclip or offer an alternative way to keep replacing my coins when they are moved.
Many thanks.
Niven