[3.27] Poor witch help

Hi everyone,
I'm a new player and this is my first league.

I've read and studied a lot, but despite that, I'm still having some issues with my "Eye of Winter" build:

1) It doesn't seem to deal enough damage
2) It doesn't seem to be resistant enough (I can't get past tier 4 on the map device)

I can't tell if I've misplaced my passives, if there's something wrong with my gear, if the problem is with my support gems, or if it's a combination of all of these.

I generated the build report with POB (although for some reason it still correctly displays "Unreserved Mana" as negative), and you can view it here: https://pobb.in/ZFN1f_Hx9zAV

Can any more experienced players tell me what mistakes I made while creating my builds (and if there's a way to fix them)?

Thank you all so much!!