Shared encrypted files do not appear in my local Nextcloud folder

Nextcloud version (eg, 20.0.5) : 21.0.1
Operating system and version (eg, Ubuntu 20.04) : Ubuntu 20.04
Apache or nginx version (eg, Apache 2.4.25) : don't know, it's running on Cloudron
PHP version (eg, 7.4) : 7.4.3

The issue you are facing:
Encrypted files that I share with a user do not appear in that user’s local Nextcloud folder.

Is this the first time you’ve seen this error? (Y/N): Y

The output of your Nextcloud log in Settings > Logging:

I cannot access it.

The output of your config.php file in /path/to/nextcloud (make sure you remove any identifiable information!):

config.php redirected me to my dashboard.

The output of your Apache/nginx/system log in /var/log/____:

I did not see a file with the word system in it in the /var/log/nginx/ folder.