Did a module update that included multiple modules, once the update was finished, config applied I got a blank page.
Ran a command to determine the issue:
PHP Fatal error: Cannot redeclare class ISymphonyServer in /var/www/html/admin/modules/isymphony/isymphony/classes.php on line 40
I deleted the directory of the isymphony module, all I got the GUI back with super high memory usage. I manually SFTP’d the module back on from a backup and had the same issue. Somewhere, something isn’t working.