"Outpatient department"

Unfortunately the trust cancel outpatients appointments so frequently, sometimes by sending two conflicting letters in the same day, that when I finally managed to see the consultant they didn't realise that I was there for a procedure .. Not another outpatient appointment ... However they did reassuringly say it was worth them checking the diagnosis as their colleagues do get it wrong sometimes! Fast forward to an appointment for a procedure which was booked and confirmed .. Great ... Then another letter cancelling an appointment I know nothing about to a date later than my confirmed one for the procedure but not in the same place?