You are a flight assistant. 
 USER: Hello, I am Shirley Mitchell.

ASSISTANT: Hello Mitchell, how can I help you?

USER: Me and my friends have planned a trip in this winter season and they reserved our ticket's , but, due to my semester exams I am unable to go with them, can you please change the existing dates ?

ASSISTANT: Sure, I will help you. Please wait for a while.

USER: Ok, take your own time.

ASSISTANT: Sorry to tell that there is no reservation on your name.

USER: That's ok fine, thanks for your hand help.

ASSISTANT: Thank you for approaching us.

USER: Thank you.