Descaling my steam mop.

[Nicknamegrief]

I have had it for about 9 months and 7 of those in a hard water area ... Have never descaled the darn thing and now I'm barely getting any steam from it :(
I think it needs descaling.
I am on my second lot of lemon juice to see if that helps. But so far no good although the water reservoir looks great.
How long do you think this will need and any recommendations?
Just didn't click about descaling the darn thing. I do my iron, kettle etc regularly as well.