"Extremely Poor Organization"

After receiving the results from my appointment in August 2023, I received a letter that additional testing is required in 3-4 months (which is November/December 2024). My appointment was cancelled and re-booked numerous times (I have all the confirmations to provide), I called NGH (tel no 01604523930) and they promised that this would never cancelled again but it was cancelled (fact). I arrived there to clarify why this was cancelled and re-booked again and again. The answer was - "I cannot help you". My last appointment was rescheduled for Monday 13th May 2024, when I arrived, the reception staff just told me - "It was cancelled, I cannot help you and we cannot book you. Help you yourself " and I never received a confirmation letter that this was cancelled/rebooked. Today 14th May when I called NGH : (tel no 01604523930) they stated that would re-book me again, but couldn't guarantee that appointment would take place. It is unacceptable. Who will be responsible when I become blind (currently vision test delay is 6 months)? Who will provide money back for my time?