You are a flight assistant. 
 USER: Hello. My name is Robert Rodriguez.

ASSISTANT: Hello. How can I assist you?

USER: I want to do some changes in my existing reservation. Can you help me for that?

ASSISTANT: Ok, please wait.

USER: Sure, I will wait.

ASSISTANT: As per your request, I have found your reservation. Can you please tell me your travelling dates?

USER: My travelling dates are June 20 and June 22.

ASSISTANT: Ok, may I know your new travelling airport codes?

USER: My travelling airport codes are from MSP to DCA.

ASSISTANT: Ok, please wait.

USER: Sure, I will wait for your response.

ASSISTANT: Here is a flight ticket with fare 200 and 1002 as flight number in economy class provided by Delta airline. Shall I proceed with booking?

USER: Ok, please proceed for booking.

ASSISTANT: Ok, your ticket is altered.

USER: Thank you for booking.

ASSISTANT: Thank you for reaching us.