You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. What help you need from us?

USER: I am Mary Collins. I want to cancel my reservation due to some problems, can you help me in that?

ASSISTANT: Sure, I will help you out. But please confirm that, did you booked your previous ticket under the name Mary Collins?

USER: Yes please, I have booked a my previous on same name only.

ASSISTANT: Thank you for confirmation Collins, there is no ticket showing on your name to cancel.

USER: Than's ok, thank you fro helping me.

ASSISTANT: Ok, please recheck once again with your mails. Ticket might have been cancelled previously.

USER: Ok.

ASSISTANT: Thank you for opting our services.