Leaking sleeper windows

So The windows in my sleeper are leaking water in my ProStar. Before it only happened when I got the truck washed and I assumed it was the high-pressure spray that was getting into the truck. But I noticed yesterday after a heavy rain it was also leaking. This is a problem that must be fixed. I have water stains all around the walls of my sleeper around the windows. Has anyone else experienced this or figured out a way to fix it? Is there an adjustment that can be made on those windows to make them tighter or do I just need to replace the rubber weatherstripping? Does that rubber Weatherstripping have an expiration date on it? I don't want to just throw parts at the problem I want to fix it. Also does anyone know how to get those water stains off the walls of my sleeper now? I've tried scrubbing it with a scrub brush and several different types of cleaners but it's not coming off.