You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I help you?

USER: I want to change my existing reservation which is done recently due to some health issues, can you please help me in this?

ASSISTANT: Sure, I can help you. Can I know your name?

USER: Sure, my name is Raymond Martin. Sorry Martinez.

ASSISTANT: Thank you. Please stay online for a while, let me check your reservation status.

USER: Sure, I will wait for your response.

ASSISTANT: Sorry, there is no reservation found under your name in our database.

USER: Ok, not an issue. Anyways, thank you for your service.

ASSISTANT: You are most welcome.