You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: Helen Thomas here.

ASSISTANT: How can I help you Helen Thomas?

USER: Due to sudden change in my trip location, I would like to change my reservation to next month. Can you please help me out with changing of my reservation?

ASSISTANT: Sure, I will help you with this.

USER: Thank you.

ASSISTANT: Wait a moment please, let me check the database and get back to you.

USER: Sure, take your time.

ASSISTANT: There is no active reservation found under your name to change it.

USER: Oh! I think some thing went wrong in that situation.

ASSISTANT: Thank you for contacting us.

USER: Anyways, thank you for the information.