Eccentric nut eating at gantry


One of the eccentric nut on my machine’s gantry is hard to adjust, doesn’t sit flat on the gantry and is eating at the metal. Clearly that wheel is somehow misaligned, which is popping the nut out at an angle and then turning and churning at the gantry, but I’m starting to lose my temper so I thought I’d ask if someone has dealt with this, what I can try, etc.

I’ve done the 30-mins stiffening mod if that can impact anything.

Thanks