Hair dye help

[Daisypod]

I’ve been dying my hair at home for probably 20 years as I started to go grey quite young (now 49), onto dark brown
I always use semi permanent dye and often over the whole lot of hair. I now have a build up on the lengths and they are very dark brown but the roots are a lot lighter. A hair dresser told me this happens but I can’t remember the reason. I always thought that as it wasn’t permanent it would be washed out by the time in needed the roots doing. I also liked that it made my hair look better and shinier.
so what do I do now? My lengths are darker than I’d like ideally. I can’t afford to go to a hairdresser to sort it out. I’ve also in the past year lost a lot of weight and my hair has thinned drastically, luckily it was very thick before (thin hair but lots of it) so it still has a reasonable amount but I don’t want to loose anymore.
ideally I want it all to be mid brown and look healthy.
I did try a colour remover but it did nothing (I followed the instructions to the latter) and I felt I lost quite a lot of hair doing it so reticent to do it again.
Any advice or tips for me?

Anyone?

This happened to me, for the last 2 years I have only dyed my roots. The colour is now fairly even but by week 6-7 I've got quite light on top with grey reappearing. My lengths still remain the same colour as they were.

Going forward you need to just dye your roots when they need doing and not do a full head dye to avoid build up.
With your ends, it depends how drastically you want to lighten them. You could try some clarifying shampoo or Head and Shoulders to try and fade the colour a bit. If that’s not enough then you could try a different brand of colour remover. Be aware that a colour remover, if it works effectively, will usually leave you with patchy orange hair that will then need correcting. Your hair will also be left more porous, so if you then dye over it be aware it may go darker than expected.
Your other option to lighten would involve bleach but I wouldn’t recommend you do this yourself and it would affect the condition of your hair.
If it were me, I would do a few clarifying shampoos, then dye my roots only with a shade darker than normal to correct the light roots/dark ends balance. Hopefully then as it all gradually fades it will be more even.
If your roots are becoming more grey and resistant, you may need to use a permanent dye if semi permanent isn’t enough.