I think this is tennis terminology. Here, I think it would mean that you have won the match while on the receiving end (your opponent was serving). I don't know a lot about tennis though. Outside of that context, I have no idea. Here is an English glossary of tennis terms if it is indeed about tennis. en.wikipedia.org/wiki/Glossary_of_tennis

I've found it in a text for internships where the trainee has to pay a fee if he "gets break match". Out of the context I would say that this means if he doesn't want to do the internship any longer he would have to pay that fee. The only sentence of the text that I could give is the following: TN fee means a TN break match fee. I just thought maybe it would be a common expression and wanted to substantiate what exactly this expression means :)