The customer is Unable to Submit a RFC. He is receiving errors like this one:
ServiceDesk 8.5 RU4
That exception received, "CategoryName is null or empty" means the Change Ticket didn't get properly created as every process creates a DocumentCategory for keeping any attached documents.
Try the following:
1. Reboot your ServiceDesk server in order to stop any thread that could be hanging.
2. Check if:
The automation library is either you got multiple automation libraries for the same project
OR you got mismatched versions (you need to compare the build versions of the automation libraries in the CustomLib folder and the ProcessManager\Plugins\Rules folders and see if there are the same or different).