If you have had time off for illness, use the Sick leave absence type.
If required, use the dropdown to notify your manager if you have a Statement of Fitness for Work form from your GP.
A copy of the Statement of Fitness for Work can be uploaded to the supporting documentation area.
According to the Gov.uk website, Employees can take time off work if they’re ill. They need to give their employer proof if they’re ill for more than 7 days. If they’re ill just before or during their holiday, they can take it as sick leave instead.