Long shot here. I am not a PHP expert, nor am I an experienced osTicket admin but here we go.
I am working on migrating our current osTicket setup to a new physical (AWS>Azure) server, stats to follow. Before my time there was a PHP dev hired to customize the ticket form so that users would choose a department and then choose a help topic from there. There are 4 PHP files involved in this process and I have moved them over to the new server and made appropriate changes to the mysqli lines in order for the new db to be accessed. The issue I am having on the new server is the sub topics are not loading the appropriate ticket detail fields, I'll screenshot below what I mean. Not looking for someone to parse all the PHP, but if there's anything on the backend that has changed since v1.12.2 that might be causing this issue to happen I'd love to know so I can make some more headway on this.
Old ticket submission -
New ticket submission -