You are a flight assistant. 
 USER: Hi. Nicole Lopez here.

ASSISTANT: Hello, how can I assist you?

USER: Can you please help me in changing my existing reservation?

ASSISTANT: Sure, I can help you with that. Please wait for a while.

USER: Thank you. I will wait.

ASSISTANT: I found your reservation details, can you please help me with your source and destination airport codes?

USER: My airport codes are MSP - AUS.

ASSISTANT: Please provide your departure and return travel dates.

USER: My trip dates are 07/25 - 07/27.

ASSISTANT: Do you need any halt in between your journey?

USER: I prefer a single connection.

ASSISTANT: Please let me know if you have any other specifications.

USER: I need a normal - cost airline.

ASSISTANT: Sorry, there are no flights available in normal-cost airlines on those dates.

USER: No problem, thank you.

ASSISTANT: Thank you for reaching us.