Handling unintended input

Hi, I’m just trying to get the weather bot running.
It’s working fine so far but I want to handle the “city not found” error in a reasonable way.
If a user enters a city which is not found, the bot should say:
“I did not find {{event.payload.text}}. Please enter another city”
Is there a “standard” way to handle such issues?

Best,
Christoph