Colour build-up, any tip to prevent?

[Lockoptimisten]

Dear specialists!
i use a high pigment dye every month (not damaging/permanent) to make my hair look fresh and vibrant. But I feel that after a couple of times reapplying the colour gets darker and less shiny. I try to avoid applying the hole hair and just focus on my growth but still. Does anybody else have similar experiences? The hair doesnt feel damaged just kind of overcoloured our something.:rolleyes::rolleyes:
I loved the first time i put the colour on and would love to have it that natural everytime but i dont know how to accomplish that. My english is not the best but i hope you at least understand what i mean;)

[SkyChild]

I know what you mean and have had this.
I think maybe just really only do the roots and none of the rest of the hair until it's properly faded. Maybe also your shampoo doesn't fade the colour quickly either.
Have you tried other brands of dye? Maybe a cassia gloss would bring back the shiny without darkening the colour?

[rohirrrims]

If it is a deposit only dye have you tried using a clarifying shampoo?

ETA - Your English is fantastic!

[Firefox7275]

Is in semi permanent (no peroxide or alkaline agents) or demi permanent (contains some peroxide)? Are you only getting the build up where you are overlapping with the previous months dye?