You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I aid you?

USER: My name is Kenneth Lopez. I would like to travel from IAH to IAD, could you help me out?

ASSISTANT: Sure, I am here to help you out. Please share me your trip dates.

USER: My preferable dates are from 08/20 to 08/22.

ASSISTANT: Sorry Lopez, here I didn't find any flights on your required dates.

USER: That's ok. Thank you for your time.

ASSISTANT: Thank you for reaching us.