I have seen many videos on Youtube on how to bleach knots but I was still hesitant about trying it out myself. I bleached the knots and guess what... the knots were overbleached and it came out brassy.
See for yourself :(
So I went back to Youtube to search for ways to fix overbleached knots on a closure. This is the video I used to correct my closure:
My Closure after I fixed the overbleached knots:
A much easier and super quick solution is to use Colorful Red Out Shampoo Treatment. I would have tried this method but I could not find the product anywhere in my area. If you can find it where you live then this is a faster method. It is also available online HERE