There are certain types of user input errors, that are known - they’re handled by the server, but the client delivers them wrapped by redundant generic message.
There are two sentences saying the same thing. The first one is localised and user friendly, while the second one comes from the SQL subsystem. The second one shouldn’t be shown.
The “Server errorr occurred” message is only used for unhandled server errors. There is a UserOrigamException class that if implemented, hides this additional message on the client. It should be used or implemented on all server error messages reacting to user errors.