Hi @JuliaMora15110, I hope I got your question correct:
Can you please go to your Alerts section and click on the alert you want to have more details on, on "Observation"
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And then you see the alert again with the time stamp where you can click on "Session Traffic"
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Is the next page what you're looking for?
You can also go to this with Monitor > Event Viewer, but then you have to manually drill down to your alert.
Hope this helps,
cheers