A trigger requires an action as in “it is happening now” to activate
Official docs: Triggers — Zammad Admin Documentation documentation
If you are looking for escalations, SLAs are the way to handle escalations
Official docs: SLAs — Zammad Admin Documentation documentation
It looks to me that you are looking for something like a scheduled task as in “verify every X if tickets have conditions Y and do Z”
Like e.g. where I check every work-day at 10:30 if there are tickets that have the condition last_contact set to after relative 2 weeks
In this example, the owner (agent) and the customer get an email which reminds them that nothing has happened for two weeks
Official docs: Scheduler — Zammad Admin Documentation documentation
If this does not help, better listen to @MrGeneration and get commercial support from the Zammad team.
Best,
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