Tattie Bogle:

In cases where one of you receives an invitation to get a vaccine and another is not, despite obvious criteria for being so vaccinated, it might avail to go together and see what happens. I was vaccinated on a walk-in basis, and there was a wait-listed line of people who would fill in because the vaccine was thawed out on a batch basis and the medical folk were not going to waste any doses.

Just a thought.