You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I help you?

USER: Will you please assist me to change my existing reservation as my plan to meet my friend got postponed?

ASSISTANT: Yes, can you share me your name?

USER: Charles Martinez.

ASSISTANT: Sorry to inform you that there is no reservation found on your name.

USER: No issue, Thank you for the information.

ASSISTANT: Thank you for reaching us.