How to keep surger needle from falling out?

I have a surger that I've been using, and on occasion the left needle would completely come out of the socket. This wasn't much of an issue because I could just put it back in and keep sewing. However, all of the sudden it happens again, and instead of it now being fine, it continuously comes out and I can't even get 1 stitch done without the issue happening again and again. How do I fix this so I can surge again?