Hello here!
One solution could be to either use triggers to do this automatically or macros if you want the agent to double-check and do the click
With triggers set correctly it can recognize the domain
of the sender and, besides other things, set the specific customer
With macros the agent still opens the ticket yourself and then uses the bottom right button to activate the macro, which can change customer and other attributes
More details in the documentation
- Triggers — Zammad Admin Documentation documentation
- Macros — Zammad Admin Documentation documentation
Best,
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