stuntnaz said..
Tap the knot with a hammer on a flat surface
Roll it over and keep tapping the knot keep repeating this process and the knot will get so soft you will get it with your fingers
Yep agree with stuntnaz and cbulota with this one... I lightly tapped and rotated the knot in my line using a plastic faced hammer against some solid timber for what felt like hours but really it was probably 30 mins. I also kept wetting the knot with ph neutral soapy water while tapping away- patience will see the knot came undone with your fingers. I would refrain from trying to stick sharp objects in the knot to separate the lines as you might cause damage. Good luck and remember paaaaatttience...