If you use swim-lanes, I think you don't need any wait mechanism. It's implied that the Customer Representative has to be ready to do the task.

Here's a suggestion done with PlantUML/PlantText:

If you use swim-lanes, I think you don't need any wait mechanism. It's implied that the Customer Representative has to be ready to do the task.

Here's a suggestion done with PlantUML/PlantText:

EDIT Here's another suggestion (source) with a more explicit wait semantic that allows for hanging up.