The Exact Online journal is divided into sections for each available financial period, with each period corresponding to a month of the year.

If you received an error stating 'The financial period was not found in your accounting software', it means that your financial period is closed.

To access the financial periods overview, navigate to your Exact Online Master Data and select the period-date table. From there, choose the appropriate year and ensure the financial period is open. If it is not, make the necessary adjustments.

In Exact: Overview | Financial years > Financial year > Period 

Please make sure that the financial date of the Journal in which you plan to allocate this expense is currently OPEN.

After making adjustments, it is important to disconnect and reconnect to Exact, then synchronize again to ensure that the data is synced correctly.