Problem with printing with LibreOffice API

I receive bug to fix. Somebody write program which call printing document from other app. Jar with this program is on Microsoft Server for a few users. Problem is when one of user want print and other too in the same moment. For example user1 click print and have print preview, at the same moment user2 do the same action and he don’t have print preview, because print prieview of document user2 is displayed on screen user1. I don’t know where is bug, in code or blame is Libre. I try disable lock file like here. I don’t have more idea how fix this.

What is the code that uses the API? Do users use the same profile? How could one answer a question without any basic information?