You are a flight assistant. 
 USER: Hello, Gary Lopez here.

ASSISTANT: Hello, how may I help you?

USER: I want to change in the dates of reservation, as some more friends are need to join us if I am changing the dates, can you please help me?

ASSISTANT: Sure, please give me a moment, I will let you know the possibility.

USER: Ok.

ASSISTANT: Sorry, there is no reservation found on your name.

USER: No issues, thank you for information.

ASSISTANT: Thank you for reaching us.