An error occurred while trying to connect (An error occurred in the document service: Error while downloading the document file to be converted.) (version 8.0.1.31)

An error occurred while trying to connect (An error occurred in the document service: Error while downloading the document file to be converted.) (version 8.0.1.31)
An error is thrown when integrating onlyoffice into nextcloud. The sites are transferred to https, if you turn off https and transfer them to http, then onlyoffice will work.
The certificates are self-signed, since there is no domain and Internet, everything goes through the local Internet.
Please help me
Exception: Возникла ошибка в службе документов: Error while downloading the document file to be converted.

  1. /var/snap/nextcloud/41512/nextcloud/extra-apps/onlyoffice/lib/DocumentService.php - line 103:OCA\Onlyoffice\DocumentService->processConvServResponceError()
  2. /var/snap/nextcloud/41512/nextcloud/extra-apps/onlyoffice/lib/DocumentService.php - line 444:OCA\Onlyoffice\DocumentService->getConvertedUri()
  3. /var/snap/nextcloud/41512/nextcloud/extra-apps/onlyoffice/lib/Controller/SettingsController.php - line 192:OCA\Onlyoffice\DocumentService->checkDocServiceUrl()
  4. /snap/nextcloud/41512/htdocs/lib/private/AppFramework/Http/Dispatcher.php - line 230:OCA\Onlyoffice\Controller\SettingsController->saveAddress()
  5. /snap/nextcloud/41512/htdocs/lib/private/AppFramework/Http/Dispatcher.php - line 137:OC\AppFramework\Http\Dispatcher->executeController()
  6. /snap/nextcloud/41512/htdocs/lib/private/AppFramework/App.php - line 183:OC\AppFramework\Http\Dispatcher->dispatch()
  7. /snap/nextcloud/41512/htdocs/lib/private/Route/Router.php - line 315:OC\AppFramework\App::main()
  8. /snap/nextcloud/41512/htdocs/lib/base.php - line 1068:OC\Route\Router->match()
  9. /snap/nextcloud/41512/htdocs/index.php - line 38:OC::handleRequest()

@onlyoffice have you disabled this option in onlyoffice config app nextcloud ?

maybe something wrong in your HTTPS config file

Same issue here, and it does not work with disable certificate verification too. Try to update to the latest version of Nextcloud 28.0.4 and the issue is solved. It is working with both enable and disable certificate verification.