When an employee is paid Annual Leave they'll automatically be paid at the highest of their Average Daily Rate or Ordinary Daily Rate.
Ordinary Daily Rate is the average daily rate over the last four weeks, normally this rate will be the highest.
Average Daily Rate is the average daily rate over the last 12 months.
The exception to this is for the 12 months after an employee returns from parental leave you pay the Average Rate.
For a further breakdown on these rates you can select the blue information icon on the Annual Leave Taken line to see exactly how these rates are being calculated.
If PayHero doesn't have enough history to calculate these leave rates, or if you disagree with the calculated rates, you can change them using the Days dropdown to change the payment units to Hours. Doing so will allow you to manually set the total days, hours, and hourly rate the leave should be paid for.
For more information on Annual Leave payments see this article from MBIE.