The cause:
One of more expenses that you're trying to export has a payment date that falls within a locked period.
The solution:
If the expense in question is a Pleo card expense:
Open the locked period in Fortnox.
Or:
This option is only really feasible if you've only got one or two expenses that need exporting. In Pleo, you could disconnect from Fortnox, change your accounting system to the custom file format, and then export (i.e., download) the missing expenses from Pleo and add them manually in Fortnox. The final step would be to disconnect from the custom format and then reconnect to Fortnox. Please bear in mind that the first option, if feasible, is substantially faster and easier.
If the expense is a Pocket expense:
Change the date in Pleo so that the expense falls within an open accounting period:
