>>1010018
If you'd be willing to give it a quick look maybe, I've uploaded the model:

https://files.catbox.moe/e17qyr.rar

The thing is, it strangely works for some parts I have done like the front hair. I have not deviated from the method at all.
I'm just following a character creation tutorial right now.

The steps were as follows:
>Create a proxy object, put it on the approximate correct location
>Add the necessary bones to it, snap them to the object
>Apply all transforms
>Assign the weight paint manually by clicking the vertex and assigning a 1 to the top to the "head" group, and the bottom to the corresponding hair control bone
>At this point I confirmed the way the proxy mesh moves, which seemed fine
>Go to the actual hair object, add a data transfer modifier
>vertex data -> vertex groups -> nearest face interpolated
>generate data layers

The part thats currently not working no matter how many times I carefully step by step redo it according to the tutorial would be the back hair part. The tutorial would be the following:

https://www.youtube.com/watch?v=et1L4Bsa8Rg

The steps I noted were all taken within the first 6 minutes.

I'm not sure if this is an issue of using a newer version or not (I am on 4.4), possibly just something stupid on my end.