Hi Jonah,
This is because you have already pre-booked all the enhancements available on your upcoming holiday, so there would not have been any available. I have flagged this with the team so we can improve this in the future.
I have had our IT guys look into this and they can't seem to do it either. They are going to do some digging for you, so just avoid logging in for a couple of days. Also, you will have received a 'password reset' email when they looked into this, so use this one when you next log in and you will be able to change your password back once you're in.
I will keep you updated with our progress.
Kindest regards,
Monty