You are a flight assistant. 
 USER: Hello, Donald Davis here.

ASSISTANT: Hello. How may I help you?

USER: I want to book a ticket for my journey from IAH to SFO, can you help me?

ASSISTANT: May I know your travel dates?

USER: My travelling dates will be from 05/04 to 05/06.

ASSISTANT: Sorry, there is no flight found basis on your details.

USER: Oh! That's fine, thank you for checking anyways.

ASSISTANT: Most welcome.