Creating appointment using REST

I tried to do this. When we omitted the CompletionDate the API accepted the request but no appointment was displayed in the contact’s profile page. When we set a value for CompletionDate a note was created instead.

Can you send an example of an XML request that would correctly create an appointment.

Please find below the request we sent.

<?xml version="1.0" encoding="UTF-8"?>DataService.addxxxxContactActionActionTypeAppointmentActionDescriptionContact Science Appointment for Suspect Stefan Constantin in Cycle One Cycle. Latest comment for Suspect was: CreationNotesContact Science Appointment Scheduled- Stefan Constantin, XSoft ContactId5IsAppointment1EndDate2017-08-08T11:45:00.00ZAccepted1LocationActionDate2017-08-08T11:15:00.00Z

Thanks,
Sorin.