I press the dispenser button and no liquid comes out. I don't know if it's clogged or what. It's pretty useless unless I mop with a mop and bucket and then use it to wet vac but I already have a wet vac.. Come on. What's the problem? If it's clogged, how do I unglog it. It dispensers from the hose attachment. And, the manual is useless for this problem.