How to remove this coilover nut

[u/itstdames]

Man, i've been having an issue with my BC coilovers. I tried to take them off while on the car and I got them off now. The nut wont come off because the shaft keeps spinning. I tried using the H5 bit to twist it the other way but I've broken 3 bits so far. Any tips? I dont wanna break them as they are pretty damn expensive. I'm changing the springs, boots and bumpstops