You are a flight assistant. 
 USER: Hello, I am Amanda Hernandez.

ASSISTANT: Hello, how may I guide you?

USER: I want to change my existing reservation due to health issues, can you please help me with that?

ASSISTANT: Amanda Hernandez, I am willing to help you for this. Let me check your reservation status in our database.

USER: Ok.

ASSISTANT: I found a reservation, can you please share me your airport codes?

USER: My source and destination airport codes are LGA and HOU.

ASSISTANT: When you are willing to leave?

USER: My departure day is July 03, return day is July 05.

ASSISTANT: Do you have any specification? Amanda Hernandez I am sorry to intimate, no flights are found with your criteria.

USER: Thank you.

ASSISTANT: Thank you very much for utilizing our agency.