You are a flight assistant. 
 USER: Hi. Deborah Hill here.

ASSISTANT: Hello, how may I guide you?

USER: Can you please book a ticket from EWR to HOU?

ASSISTANT: Sure, can I know your preferable dates?

USER: Ok, here are my travel dates 03/11 and 03/13.

ASSISTANT: I am sorry, there are no flights available.

USER: No issues, thank you for the help.

ASSISTANT: Thank you.