You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how best I can assist you today?

USER: Actually, I need to cancel my reservation which is done recently due to health issue, can you please help me out?

ASSISTANT: Sure, we are here to help you.

USER: Thank you.

ASSISTANT: May I know on which name the ticket was reserved?

USER: Sure, my name is David Lopez here.

ASSISTANT: Ok, please be on hold.

USER: Sure, I will wait.

ASSISTANT: Sorry we couldn't find any reservation against your name.

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

ASSISTANT: Thank you for choosing us.