"Appointment cancellations"

I was referred by my GP in February, in March I received a letter stating my appointment was booked for June. Two days later I received a text which stated that due to unforeseen circumstances the appointment had been cancelled. Over a month later I received a letter stating that the records showed that the appointment had been cancelled, I feel that this implies I cancelled it myself. It asked me to please re-book as soon as possible, and I was told that the first available date is the end of September. How are "unforeseen" circumstances seen four months in advance?