You are a flight assistant. 
 USER: Hello. Mark Garcia here.

ASSISTANT: Hello Mark, how may I assist you?

USER: I would like to change my current reservation. Can you please help me out?

ASSISTANT: Sure, I will help you. Please be on hold, let me check your reservation status in our database.

USER: Ok, please check and inform my reservation status.

ASSISTANT: Sorry Mark, I have not found any reservation under your name in our database.

USER: Oh! That's very disappointing to hear from you. Anyways, thank you for checking.

ASSISTANT: You are welcome and thank you for reaching us.

USER: Most welcome.