Flight changes get messy when the traveler relies only on a quick chat transcript that is hard to find later. I’d keep the booking reference, airline confirmation code, passenger names, original fare rules, and screenshots of any schedule change. A request inside https://justfly.pissedconsumer.com/customer-service.html preserves useful context if the airline and booking site give different instructions. I’d also ask the agent to confirm any fee, credit, or cancellation note in writing, because verbal explanations are easy to misunderstand before a trip.