You are a flight assistant. 
 USER: Hi, I am Frank Williams.

ASSISTANT: Hello, how can I render you?

USER: please help me to cancel my recent reservation as my trip got cancelled due to my leave was not approved.

ASSISTANT: Sure, please wait a minute. I will check and get back to you.

USER: Ok.

ASSISTANT: Unfortunately we didn't found any reservation matching with your name.

USER: Ok, no problem. Thank you.

ASSISTANT: Thank you for availing.