So I'm organising secret santa at work this year and I have messed up 
I asked everyone if they wanted to be in it and also if they wanted to go to the work Christmas meal and got the replies back but one girl was off for a while for bereavement and when she got back she said she couldn't go to the meal and I thought she said she wouldn't be in the secret santa as we usually do it at the meal.
Anyway everyone got their names and have started buying their presents but she has now said she thought she was in the secret santa.
What do I do???