A few years ago I had the same problem. The bolts holding the lock to the side panel had vibrated loose, and dropped out. At the time, I posted a topic advising people to check them. What you need to do is to get a length of wire, such as a wire coat hanger, make a hook in one end and then hook the cable which is attached to the lock. Pull the lock back into the hole and while holding it, get the key in and unlock the saddle. Not as easy as it sounds, but with perseverence I managed it. Then you can remove the side panel and rebolt the lock, using locktight.
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