Ramati
Please read the software prerequisites before installing/using. Our prerequisites show that only Apache (and Litespeed) and IIS are supported out of the box. We ship the software with the needed config files for Apache and IIS (.htaccess and web.config respectively) so they just work out of the box. However, NGINX doesn’t allow this so you must do manual work to get it functioning properly. With this being said you must either switch to Apache/Litespeed/IIS or go online to find a working osTicket site config with all the latest rewrite rules.
Cheers.