AudiDudi - I had the same issue with my Prism 24J. I got some plastic latches from eBay and simply used double-sided foam tape to attach them to the rig. Two are stuck to the slide-out. And yes, I did forget once, since the hatch door can only be held open when the slide is in, I opened the slide and heard a "POP" sound. Fearing the worst...went out and checked - no damage to anything. The hatch simply popped off the plastic latch. I did use only a couple of small pieces of foam tape on that one - hoping it would pull off prior to door or slide damage. Apparently I did well = since even that didn't occur! less than $10 between 5 latches and tape. 8^) ST
Two and a Hound in a 2015 Prism "B+", pushed by a 2021 Chevy Equinox.
1st 50 done, working on the 2nd pass! Somewhere over 150k miles to date
2005-2015 Roadtrek 190P, 1993-2005 Northstar Soft-Side TC, 1989-1993 Tents!