Morphy Richards Jet Steam Generator Iron 2200W Model 42271?

Hi,

I am wondering if you can help me, my steam tank iron has decided to stop working. I am a female and not very good with repairing electrical products hence seeking help online. The iron still heats up 'hot' but when I press the button for the steam it makes a loud squeal noise and just gives out a small amount of steam. I have had the iron around 4 years but its still brand new. I have changed the anti scale cartridge holder and the water filters but this is still not working like it has previously. You can hear the water coming up the pipe from the tank but I have a feeling that it is clogged with scale but dont know how I can fix this or what I can buy to unclog.

Thanks