"Public Health"

I have a primary immunodeficiency and am vulnerable to infections like covid. In early Aug. I went for my regular vaccination. Evening appointments are the only times I can come, and are very hard to access. Knowing that, I prebooked for early November in August following a date the nurse told me would be in time for my next shot. 

One day before that Nov. appointment, public health called me to say that I was "eight days too early" for the vaccination and needed to rebook. They were not able to get me in again until early December, which leaves me vulnerable for nearly a month without the vaccination. This is short-sided and pedantic in my opinion. 

I would have expected the nurse who gave me the wrong date three months ago to find a way to book me in eight days later in the evening as was my intention when I proactively booked three months ago. I feel vulnerable and frustrated. I am trying to play by their rule book and they change the rules with no regard for the personal impact and no accountability for their mistakes.