If you're away on time off (e.g.: Vacation or Parental Leave), you probably don't want NikaTime to be asking you what you did every day.
NikaTime is clever, and when you have scheduled time off for your full workday duration, she won't bother you that day.
You can schedule time off through your chat with NikaTime, or your Report Center: How do I Schedule Time Off?
NikaTime admins can set the workday duration on the Team Settings page: How do I change my team's work hours policy?