Returns a ZIP archive holding one document per requested invoice. Pass up to 50 ids, taken from /invoices/invoices/e-invoices/{format}. An archive is returned even for a single id. Ids that cannot be rendered or are not available to this account are left out of the archive and listed in SKIPPED-INVOICES.txt and SKIPPED-INVOICES.json inside it. A 200 is NOT always an archive: when none of the ids could be rendered the body is a JSON object carrying success: false and the reason for each. Check success before treating the body as a ZIP.