You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: Emily Walker here. Reserve a flight ticket that is from PHL to LAS.

ASSISTANT: Sure Walker, please share your travelling dates?

USER: Ok. My travel dates are from 07/31 to 08/02.

ASSISTANT: Walker, sorry for the inconvenience, no flights as per your details.

USER: Ok, not a problem. Thank you.

ASSISTANT: Thank you for reaching us.