Hello curlies!

I am trying to get long hair (to lower back). It's more than 3 years that I can't get an inch of growth. Hair at the back of my head are 3 inches past the level of my bra but at the top of my head doesn't grow past my shoulders
So naturally my hair have 2 layers. But the long layer has a few strands

Hair are not damaged, It's more than 4 years that I gave up any kind of heat.
I was wearing them curly (CG routine) till 2011, and the last 2 years I am doing BKT every 2-3 months. I dye them every 3-4 months

I rarely see any split ends, but when I do I take care of them.
My natural hair is a 2c-3a, medium to high porosity and a mix of medium and extra thick strands.
I am kinda into bodybuilding so my nutrition is defenetely not the problem (lots of proteins, vitamins etc)

I really don't know what to do. I am dreaming of extra long hair just like this