Trigger an Event

Hi All,

We currently have orders being placed through TOPdesk - these are logged as a simple change. Once our 3rd Party supplier confirms the order has been shipped, then send an email to us with a specific Phrase “OrderStatus: Shipped” typed into the body of the email. This updates the relevant ticket so we can see its status.

Is there a way I can set up an Event trigger to complete these tickets when we receive this status? 

I have tried to set up an event trigger, but can’t see where I can just add that phrase to trigger the event.

Any ideas would be greatfully received.

Thanks

Caroline