Your description isn't all that clear to me, so I'm guessing at what you might have.
When you say that action is the "top level", do you mean it is the parent under which the other actions are indented, or is it the first of the indented actions?
If the former, you should realize that the container (or parent) action becomes available only when all of the actions in the container have been completed.
In other words, you don't want to do this:
Instead, you should do this:
