Appointment + problem

Hello
We have been using appointment + for some time now and it has worked well. Suddenly today there are dates on our calendar showing as available when they are not. And even when I add these days as an exceptional holiday, they are still showing as available. This is a disaster for us! Please get back in touch asap to tell me how to reset this. You can see what is happening on our webpage http://selce.org.uk/energy-advice/energy-cafe/ There should only be Mondays showing for Woolwich and Tuesdays only for Catford.
Thank you, Joe