You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Charles Campbell, want to travel from LGA to HOU. Please help me in booking my ticket.

ASSISTANT: Sure, please provide your trip dates.

USER: My trip dates are from 06/13 and 06/15.

ASSISTANT: Do you have any specifications?

USER: My return time will be in the evening with 1 connection.

ASSISTANT: Please give me a moment to check for available flights.

USER: Sure.

ASSISTANT: Sorry Charles Campbell, no flights are available in the evening.

USER: It's ok, thank you for your help.

ASSISTANT: Thank you for choosing us.