You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I render you at this moment?

USER: I have made a reservation earlier to meet my friend, but due to bad weather conditions there, I have decided to meet her next time. Will you please help me in changing?

ASSISTANT: Sure, I will help you in changing an existing reservation.

USER: Thank you.

ASSISTANT: Can you please help me with your good name?

USER: Sure, this is Gary Thomas.

ASSISTANT: Ok, please stand by.

USER: Sure.

ASSISTANT: There is no existing reservation found on your name in our data base.

USER: Not an issue, thank you for your assistance.

ASSISTANT: Thank you for reaching us.