Unable to loosen IXOW Wheelguard Gravity nut
Exact same problem here. Same bike. I got it off finally by just turning really really hard using a non-torque wrench. Make sure it's rotated so that the two dots are UP (12 o'clock). If installed correctly the lock should be at 12 o'clock when wheels are on the ground. So if you installed it in the wrong orientation (i.e. lock at 2 o'clock or 9 o'clock etc), then turning it upside down will not be the correct position. So rotate the bicycle around until the two dots are at 12 o'clock.

You can see from my photo it seems that when tried to loosen it, the tab on the black washer that is suppose to be in the fork dropout rolled into the plastic dropout insert which was causing it to bind. Going to write Canyon about this to see how I can get it repaired. Same thing happen to you?

Explained in the instructions from IXOW--packaged separately from the urban manual.