As koichi commented, Useremail() does not work correctly when running Automation using Preview app as.
https://www.googlecloudcommunity.com/gc/Release-Notes/February-21-2024/bc-p/714285#M2060
In the Automation process, it seems that Useremail is always processed as the app owner’s Email.
Specifically, the Automation process cannot be tested for different logged-in users.