You can only make entries in the current fiscal year and the last fiscal year. If you need to make an adjustment for a period prior to the last fiscal year I would suggest that you work with your accountant to figure what the entry would be as at the first day of the last fiscal year. This will then allow the adjustment to roll forward into the current year.

One reason we are limited to the current fiscal year and the last fiscal year is the assumption that all years prior to that time have been report on a tax form and changes should not normally be made. However, that is the call of the accountant to amend the tax filing or maybe the taxes have not been filed yet.