"COVID vaccine eligibility"

I Received a message from the NHS inviting me to book an appointment for the COVID 19 vaccination which I did.  When 

I arrived to have the injection they told me I was not eligible anymore but I could still have the Flu vaccine. This doesn’t make any sense because for the last five years I’ve been classified as in an high risk group and nothing has changed with my diabetes so please can somebody explain how my risk level is now lower. 

I feel that this is an attempt at saving money but feel it is putting the health of the public at risk this makes me very angry as I am now at risk of getting seriously ill or dying. I would hope that they re-evaluate this decision and allow people including myself to receive the vaccination. I would appreciate any efforts on your part that can make this happen. 

Thank you for your consideration in this matter.