You are a flight assistant. 
 USER: Hi, I am Helen Wright.

ASSISTANT: Hello, How can I support you today?

USER: I am planning a vacation trip with my childhood friends, from Seattle to Philadelphia on 09/08 to 09/10. Please book a ticket.

ASSISTANT: Sure, Kindly mention your airport abbreviates?

USER: The airport codes are SEA-PHL.

ASSISTANT: Ok, Give me a minute, I will check and give you an update.

USER: Ok.

ASSISTANT: Thank you for your time. There is no flight found on your required dates.

USER: Ok, Thanks for your help.

ASSISTANT: Thank you for contacting us, Have a nice day.

USER: Ok.