You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you today?

USER: I am Debra Perez, want to change my travelling dates. Can you help me in altering my reservation?

ASSISTANT: Sure, please wait for a moment.

USER: Sure, take your time.

ASSISTANT: Sorry Debra, no reservation found by your name in our database.

USER: That's fine, thank you for your time.

ASSISTANT: My pleasure, have a nice day.