Lump Sum E allocation of back pay over several years

I have a question regarding Lump Sum E allocation

According to ATO, backpay of more than 12mths old and are greater than $1200 are to be allocated to lump Sum E and allocated to the appropriate years.  This is the example from the ATO website

• The amount that is greater than 12 months old (14 February 2021 and earlier) totals $1,500 which means it must be reported as Lump sum E because it is greater than the lump sum E threshold of $1,200. The Lump sum E component must be allocated to the appropriate financial year. $600 relates to the 2020–21 financial year and $900 relates to the 2019–20 financial year.

This is reported in STP Phase 2 as follows:

• KN tasks $1,800
• Lump sum E 2021 $600
• Lump sum E 2020 $900.

I have set up in MYOB the Lump sum pay categories for each year and tried to do the pay but am getting and error message.  How do I enter the back pay correctly?

Many thanks