Hi Mike0926
This is more common that you would think. Caused by bugs in software. AR2026 allows adjustments to prior year, however the adjustment might not flow through to all places. There are possibly other triggers as well.
The file will need to be repaired. The self-fix suggestions won't work here. MYOB should repair for free, however support seems extremely difficult to get through to. Perhaps lodge a ticket in at myaccount.myob.com - although many are reporting waiting weeks.
MYOX Services can also repair the file, MYOB repair should be free, MYOX Services would involve a fee. Contact them for more info if interested.
Regards
Gavin