You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, what can I for for you?

USER: Owing an emergence, I want to change my existing reservation. Can you help me with it?

ASSISTANT: Sure, I can help you with that. Provide your name to check your reservation?

USER: My name is Brenda Hernandez.

ASSISTANT: I regret that there is no reservation found on your name.

USER: Ok, no issues.

ASSISTANT: Thanks for reaching us, have a good day.

USER: Thanks for the help.