Sounds like the hair is not cuticle aligned. Bleach bath should help. If not, here is a tip that I have used to get through a bad patch:
At the nape, cut off about an inch of the hair to the lace.
Sew on 2 tracks of VIRGIN hair of approx. the same length.
This will keep the non-cuticle hair from rubbing against the body/clothing and you won't have to comb out the tangles every 5 minutes.
The other solutions may work also, but in the long run, I just don't deal with all that.
Also, the John Korea hair coat works magic, but is very expensive!