You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Linda Thompson, want to alter my recent reservation due to some emergency. Please help me out with that.

ASSISTANT: Linda Thompson, Please give a moment let me check the data base.

USER: Sure, take your time.

ASSISTANT: I regret to inform that, there no reservation by the name  Linda Thompson.

USER: It's ok, thank you for your help.

ASSISTANT: Thank you for reaching us.