To get a MWBC working, with both legs GF protected, I installed 2 Single Pole GFI breakers, on adjacent slots, with a handle-tie. Since there are 2 lugs for Neutral wires, and only one neutral coming in, I used two pieces of white 12 awg to wire nut to the neutral coming in.
It doesn't work, trips as soon as it's flipped on.
I even opened the circuit at the first box, (so i kknow it's not an actual ground-fault) and it still trips, even though neither leg of the circuit could possible be conducting at all!
I was told I could use 2 single-pole breakers w/ handle tie to get both legs of the circuit GF protected, but this appears to not be the case. Am I wiring it wrong? Also, how is it possible for them to both trip when neither is conducting?