[Appointments+] Appointments getting moved to 'Removed' for no reason

When an appointment is created and the status is set to Pending, within minutes it dissappeares from the Pending list and gets moved to the Removed list. If we change the status back to Pending, it goes back to the pending list but after a few more minutes it changes back to removed. Please address this urgently as my client has had enough of the problems with this plugin.