When you create a dataset from the MS Access database, several properties of the auto number fields are wrongly set. Please, set these as in the right (correct) version below:
Access databases have to be treated slightly differently than SQL data bases, because the dataset is not created correctly when the data tables are created, which in turn will not update your data set correctly once a change in an appointment is done.
This is due to a synchronization problem between the database and the dataset, where the data adapter could not update correctly the Id of the added row. Please, review the following MSDN article on how to solve this limitation: Retrieving Identity or Autonumber Values