Update to version 17 download error

I am not able to update to version 17.0.1

[ nc-update-nextcloud ]
Cannot load Zend OPcache - it was already loaded
Current Nextcloud version 16.0.5.1
Available Nextcloud version 17.0.1
Download Nextcloud 17.0.1…
Error downloading
Clean up…

My system: nextcloudpi 1.17.1

Who has an idea?

Trying again, maybe there was a timeout.
You could check for enough disk space before, to be sure, the archive can really be downloaded.