Entering a transaction using a date in a previous fiscal year
MYOB AccountEdge doesn't allow you to enter transactions in a fiscal year that has been closed.
If you really need to print reports for the previous year with corrected information, you can restore the backup you made before closing the previous fiscal year, make the needed change in the backup file and print your reports. (If you do this, be absolutely sure that you also have made a current backup of your company file - if you don't, you risk destroying your current company file and all the entries you've made since your last backup.) Once you've printed reports for the previous year, you will need to restore your current backup and make a journal entry that reflects the change you made in the earlier backup.
Also note that you are not required to close the fiscal year at any particular time, and it may be to your benefit to wait to close the year until you're certain that all transaction and adjusting entries that affect the year have been entered. (Closing a fiscal year and starting a new one)