This error most often occurs because the report was generated before the release of corrective patches — the old form simply "doesn't know" how to correctly export to JSON for this period.
The solution is simple: don't try to export an already existing report, but create Form 200 anew. After the patches are updated, the newly generated form exports to JSON correctly, without errors.
What needs to be done
1. Make sure you have the latest configuration updates (patches) installed — these are exactly what fix the export issue.
2. Don't edit the old report, but create a new Form 200 for the required period.
3. Fill out and post the new report as usual.
4. Repeat the export to JSON — it should complete successfully.
This approach has already been verified in practice: after creating a new form, the report was exported without any error messages.
Frequently Asked Questions
Can the old report be corrected instead of creating a new one?
In practice, it's more reliable to create a new form — this is exactly what solves the export issue.
Why does this error occur specifically for the year 2026?
The reason is that the report was generated before the release of the patches that updated the logic for handling this period. After the update, the new form is created taking into account the current rules.