Why does Deline say the accounting period is locked?

What do the two messages mean?

• "The accounting period for … is locked": someone locked that month after checking it, for example once its tax return was prepared. A locked month stays closed until it is reopened.
• "There's no open accounting period for …": that month has no period yet. The books open the current month by themselves; any other month needs its period first. If you may manage periods, Deline offers Open this month; otherwise it says "Ask a business owner to open this month. Your entry is still here."

A bill arrived after I locked the month. What now?

You have two choices:

• Record it in the current, open month. This is the usual way for a late bill.
• Reopen the old month: in Periods, open the month, write the reason under Reopen this period and press Reopen period. Lock it again when you are done (see Lock a month after you have checked it).

Who can reopen a month?

The owner or the accountant. Everyone else sees "A locked month stays closed. Ask a business owner how to record this entry. Your entry is still here."