How do I review a sitter who cancelled our appointment?

I had a meet and greet that went really well and we requested to have a test “stay” for two days without other dogs to see how our reactive dog would handle the situation. The sitter agreed and, after reviewing her calendar, scheduled us. She has now stated that she made a mistake and needs to reschedule. She recommended a time during the week of Halloween, which is only days before our true trip and would give us no time to find an alternative if things didn’t work out. After telling her we felt that was unprofessional, she cancelled our appointment and told us to find someone else.