Java - Swing GUI无法加载

I've been trying to learn java for a few weeks now, and I'm working on a pretty simple autoclicker. The clicker itself works, but my problem is that my GUI never shows up. The GUI runs just fine when I run the GUI file itself, but when I'm trying to run it from my main program (different file) it never shows. The clicker works fine all the time though. I'm sure the problem is something really simple that I have simply missed, but this is now my 4th day without any clue on what might be wrong with it, so decided I'd ask here.I've been trying to learn java for a few weeks