What were the circumstances? Changed seat/equipment/domicile? I know people who complained about losing their vacations when they did this or people who didn’t have enough vacation time saved up. If you don’t have enough vacation time saved up, they will cancel days from your vacation. I know someone who went on a rant for getting their vacation cancelled but they had not even read the policy and had no idea that it was normal for the vacation to be cancelled under one of the above circumstances.