The error is based on the design of the rules by the ATO.
Error states that A4 deductions cannot be more that Total of D1-D15 fields. This means amount at A4 deductions should be also shown in one of D1-D15 fields.
Working Holiday Maker income should be both entered in salary and wages and in A4.
Validation message says that "Deductions and business losses" cannot be more than sum of total deductions and losses.
This means, it should share the amount in these values too.
Also, make sure to please update this part-