tomasdetinis
Check your logs (general server logs, webserver error logs, PHP error logs, MySQL/MariaDB error logs, osTicket System Logs, Browser Console logs, etc.) for any related errors. I will say that if you are logged in as an Agent it should not be bringing you to the client portal for opening tickets. If you are logged in as an Agent and opening a Ticket on behalf of a User the URL should be scp/open.php
not open.php
.
Cheers.