"17 year old trying to reschedule COVID vaccine appointment"

My grandson needed to reschedule his 2nd dose vaccine appointment. Within his vaccine letter it states this can be done online so he registered online and tried to reschedule. No appointments despite trying all dates to November at 4 different sites on any day at any time. 

Called the helpline and while waiting to speak to someone one of the recorded messages states: If you are over 18 you can change your appointment online. Why would this information not come up online when you register with your date of birth? Why do you need to be 18 to reschedule online? 

My grandson couldn’t hold on the line long enough to speak to someone so I did. Spoke to a really nice girl who didn’t know you had to be 18 to reschedule online. She apologised for being unable to reschedule his appointment because it needs to be from 18 October onwards. These appointments have not been released yet. 

I also listened to the recorded messaging telling people to check social media for drop in sites. I did so and there were none in Greater Glasgow and Clyde today.