Slide works its way out while stored.

Hi, The last few times when I picked up our 5th wheel from where we store it, the bottom of the bedroom slide was out by four inches, while the top was all the way in. This happens over a week or two period when the trailer is not in use. When I push the switch to retract the slide, it does not pull the bottom in, but if I extend it a bit, and then retract it, it works as it should.

Anyone have a similar experience, or have a suggestion on what could cause this?

The 5th wheel is a 32ft 2011 Montana Mountaineer with two slides.

Thanks