Hi Paul,
What is the ACW method you are using?
When using the optional method if the agent closes the browser before complete ACW, that person will be On Queue(Interacting) for the system. On the next day, the wrap-up code will be required to complete the interaction.

If you use Time-boxed ACW method, after the ACW time the interaction is disconnected and the agent status is set to Offline.
You can monitor the queue activity and try to disconnect the interactions.
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Paulo Mesquita
Spark NZ Trading
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