Miscommunication is still a natural part of appointment setting. Even in an age where technology vividly communicates our thoughts, users themselves still mess up with those very same devices. Words get chopped. Schedules get bugged. A bit of correction and repetition will always be in order at some point in your campaign.
But exactly how and how often do you have to clean up such a mess? It’s that not easy to always dive into your records and change information. Eventually, you’ll just have to push through regardless.