You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you today?

USER:  I am Mary Green want to change my reservation owing an emergence in family. Can you help me in changing my ticket?

ASSISTANT: Please give me a moment.

USER: Ok.

ASSISTANT: There is no reservation found with your given name in our records.

USER: Ok, no issues.

ASSISTANT: Thank you for choosing us.

USER:  Thank you for availing me,.