Hair woes- please advise re hair colour!

[Maroon1]

I have long fine mid/ dark brown hair naturally however for the last few years I've been using a semi permanent darkest brown hair colour so now my hair colour is practically black.
I want to revert to dark brown however my lengths & ends won't fade from black. My roots are the colour I want.

I was told to use head & shoulders but it hasn't budged the color on the lengths at all. Now I'm in a mess as my greys are twinkling at me.

Do I get a colour stripper? What to do?

Colour b4

Try using fairy washing up liquid the green one not sure why it works but i was told to do it before an made my colour fade so worth a try An just shampoo an condition as normal after

Please go to a hairdresser! A stripper is bleach and it could all go horribly wrong if you try to do it yourself! IME you can't use the harsh shampoos/ washing up liquid where there is more than one application of hair dye. I would advise you see a hair stylist once to get the cookout you want and then just touch up yourself at home!

*colour