Just received a text. Seems fishy.
Dear patient, we will shortly be commencing our covid vaccination campaign. If you DO Not wish to have this vaccine please reply Decline and we Will update your record. You will still be contacted to be offered the flu vaccine.
Alternatively decide you didn't ask to have to get involved to get your right not to take part, so ignore and let them work out why their system is failing.
Like too many things these days, if there is a default state those in control ensure it is the wrong one.
It would depend on where it came from. Your own doctor's practice, the local health authority, the whole country. The smaller the circulation, the less chance other AB people would get it. But you would expect any genuine sender to have identified themselves.
Why not phone your doctor and ask them?