You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: Sandra Young here.

ASSISTANT: How may I help you?

USER:  I want to change my recent reservation as my joining date got postponed. Can you help me in changing?

ASSISTANT: Ok, please wait.

USER: Ok.

ASSISTANT: Sorry no reservation found on your name.

USER: That's ok, thank you for checking.

ASSISTANT: Thank you for reaching us.