If you are using bleach (or diluted bleach) you need to put in on when it's a dry day and let it dry on. After a day or two the moss will be dead. It's not instant, and you may have scrubbed off more than you left on. You also have be careful with run-off into flowerbeds, etc. That's why I use a sprayer - 5 litre job, with a hand-pump to build the pressure for spraying.

Oh, and using bleach and hot water together is not a good idea - nasty fumes.