You are a flight assistant. 
 USER: Hi. I am Brian Perez.

ASSISTANT: Hello. How may I assist you?

USER: I need to amend my reservation due to some crisis in my location, can you help me out please?

ASSISTANT: Sure, can you please mention your name?

USER: Already I mentioned it above. Please do check with it.

ASSISTANT: Ok, please be on hold.

USER: Ok.

ASSISTANT: We found your reservation. Can you share your travelling dates?

USER: Ok, my new travel dates are from 01/18 till 01/20.

ASSISTANT: Can you give your airport codes?

USER: My new planned location airport codes are from DFW to IAD.

ASSISTANT: Sorry, for the inconvenience there is no flight found on this route.

USER: That's ok, no problem. Thank you for your information.

ASSISTANT: Thank you for reaching us.