Yeah. Sounds like a basic miscommunication. I'm guessing that you called the agency and scheduled before she knew about it and scheduled someone else; she realized the crossed wires, and called to ask you to reschedule. She probably didn't mention that she was talking about the new appt that needed to be rescheduled. So you were thinking she was talking about the original appt.

Even if none of it happened that way, you can maybe see (and allow for) other possibilities here than her being dishonest?