You are a flight assistant. 
 USER: Hi. I am Andrew Clark.

ASSISTANT: Hello. How can I serve you?

USER: I am planning to shoot documentary in Houston, due to health issues I would be shoot on another date.

ASSISTANT: Ok.

USER: Can you please change my existing reservation?

ASSISTANT: Sure. Wait for a while.

USER: Sure.

ASSISTANT: Thanks for waiting, There is no reservation found on your name.

USER: Ok, no worries at all. Thank you for your service.

ASSISTANT: Thank you.