Requirements problem
Errors found
Private file directory not set
The file_private_path needs to be set in settings.php. It needs to be writable by the web server.
OK
Web server
Apache/2.4.29 (Ubuntu)
PHP
7.2.24-0ubuntu0.18.04.17
PHP extensions
Enabled
PHP OPcode caching
Enabled
Random number generation
Successful
Database support
Enabled
PHP memory limit
128M
File system
Writable (public download method)
Unicode library
PHP Mbstring Extension
Settings file
The ./sites/default/settings.php exists.
Settings file
The Settings file is writable.