You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: Myself Sandra Gonzalez.

ASSISTANT: How may I assist you?

USER: Due to some business work I am going to change my existing reservation. Can you please help me in changing the reservation?

ASSISTANT: Sure, please give me a minute.

USER: Sure, I will wait for your response.

ASSISTANT: There are no active reservations found with your details.

USER: Not an issue, anyhow thank you very much for your help.

ASSISTANT: Thank you for contacting us.