Hair not locking after almost 10 months

I cut my dreads in 2010 (backcombed and crocheted) and now I wanna do them again with the neglect method.

Since I've had my dreads for a while I got used to not combing them. Since 2010 I probably combed them about 5 times. Especially since I gave birth in October (so nearly 10 months), I haven't combed my hair at all. I wash them twice a week with a natural organic tea tree shampoo and no conditioner. I only got a small dread in the back and only because I had someone massage my head a couple times. The rest of my hair is super soft, not even tangled, and does not seem to wish to lock any time soon.

Am I doing something wrong? I shampoo them well and rub them in the shower and rinse out really well. I use no products, don't even use my fingers to go through them. Is it the shampoo? Should I start with the soda wash?

Any tips appreciated!