First let me say welcome to the new world. It's always full of questions, so feel right at home!!
And then there does bring some questions as to what exact brand levelers yu have and what they might look like. HWH can Lippert are a couple big names, so if you can find anything like that or add to it, that is a good place to start.
Meanwhile, there might be a couple things to mention that might help.
How about the fluid in the hydraulic fluid tank? Has it been checked for correct level?
Second might be to look/think about if there are "return springs" on your type? Do they have big coils around the shaft that help to draw the base back up? This can get weak, so that they don't get it done----if you have that sort, so maybe give us any more info you might have?
I see down on about page 62 that there are two different chassis, one Ford and one workhorse, so knowing which may help?